invoice2 (16jul17)

git-svn-id: svn://tug.org/texlive/trunk@44821 c570f23f-e606-0410-a88d-b1316a301751

9 files changed, 2228 insertions, 0 deletions

diff --git a/Master/texmf-dist/doc/latex/invoice2/LICENSE-gpl-3.0.md b/Master/texmf-dist/doc/latex/invoice2/LICENSE-gpl-3.0.md
new file mode 100644
index 00000000000..2a99aeee332
--- /dev/null
+++ b/Master/texmf-dist/doc/latex/invoice2/LICENSE-gpl-3.0.md
@@ -0,0 +1,675 @@
+### GNU GENERAL PUBLIC LICENSE
+
+Version 3, 29 June 2007
+
+Copyright (C) 2007 Free Software Foundation, Inc.
+<http://fsf.org/>
+
+Everyone is permitted to copy and distribute verbatim copies of this
+license document, but changing it is not allowed.
+
+### Preamble
+
+The GNU General Public License is a free, copyleft license for
+software and other kinds of works.
+
+The licenses for most software and other practical works are designed
+to take away your freedom to share and change the works. By contrast,
+the GNU General Public License is intended to guarantee your freedom
+to share and change all versions of a program--to make sure it remains
+free software for all its users. We, the Free Software Foundation, use
+the GNU General Public License for most of our software; it applies
+also to any other work released this way by its authors. You can apply
+it to your programs, too.
+
+When we speak of free software, we are referring to freedom, not
+price. Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+them if you wish), that you receive source code or can get it if you
+want it, that you can change the software or use pieces of it in new
+free programs, and that you know you can do these things.
+
+To protect your rights, we need to prevent others from denying you
+these rights or asking you to surrender the rights. Therefore, you
+have certain responsibilities if you distribute copies of the
+software, or if you modify it: responsibilities to respect the freedom
+of others.
+
+For example, if you distribute copies of such a program, whether
+gratis or for a fee, you must pass on to the recipients the same
+freedoms that you received. You must make sure that they, too, receive
+or can get the source code. And you must show them these terms so they
+know their rights.
+
+Developers that use the GNU GPL protect your rights with two steps:
+(1) assert copyright on the software, and (2) offer you this License
+giving you legal permission to copy, distribute and/or modify it.
+
+For the developers' and authors' protection, the GPL clearly explains
+that there is no warranty for this free software. For both users' and
+authors' sake, the GPL requires that modified versions be marked as
+changed, so that their problems will not be attributed erroneously to
+authors of previous versions.
+
+Some devices are designed to deny users access to install or run
+modified versions of the software inside them, although the
+manufacturer can do so. This is fundamentally incompatible with the
+aim of protecting users' freedom to change the software. The
+systematic pattern of such abuse occurs in the area of products for
+individuals to use, which is precisely where it is most unacceptable.
+Therefore, we have designed this version of the GPL to prohibit the
+practice for those products. If such problems arise substantially in
+other domains, we stand ready to extend this provision to those
+domains in future versions of the GPL, as needed to protect the
+freedom of users.
+
+Finally, every program is threatened constantly by software patents.
+States should not allow patents to restrict development and use of
+software on general-purpose computers, but in those that do, we wish
+to avoid the special danger that patents applied to a free program
+could make it effectively proprietary. To prevent this, the GPL
+assures that patents cannot be used to render the program non-free.
+
+The precise terms and conditions for copying, distribution and
+modification follow.
+
+### TERMS AND CONDITIONS
+
+#### 0. Definitions.
+
+"This License" refers to version 3 of the GNU General Public License.
+
+"Copyright" also means copyright-like laws that apply to other kinds
+of works, such as semiconductor masks.
+
+"The Program" refers to any copyrightable work licensed under this
+License. Each licensee is addressed as "you". "Licensees" and
+"recipients" may be individuals or organizations.
+
+To "modify" a work means to copy from or adapt all or part of the work
+in a fashion requiring copyright permission, other than the making of
+an exact copy. The resulting work is called a "modified version" of
+the earlier work or a work "based on" the earlier work.
+
+A "covered work" means either the unmodified Program or a work based
+on the Program.
+
+To "propagate" a work means to do anything with it that, without
+permission, would make you directly or secondarily liable for
+infringement under applicable copyright law, except executing it on a
+computer or modifying a private copy. Propagation includes copying,
+distribution (with or without modification), making available to the
+public, and in some countries other activities as well.
+
+To "convey" a work means any kind of propagation that enables other
+parties to make or receive copies. Mere interaction with a user
+through a computer network, with no transfer of a copy, is not
+conveying.
+
+An interactive user interface displays "Appropriate Legal Notices" to
+the extent that it includes a convenient and prominently visible
+feature that (1) displays an appropriate copyright notice, and (2)
+tells the user that there is no warranty for the work (except to the
+extent that warranties are provided), that licensees may convey the
+work under this License, and how to view a copy of this License. If
+the interface presents a list of user commands or options, such as a
+menu, a prominent item in the list meets this criterion.
+
+#### 1. Source Code.
+
+The "source code" for a work means the preferred form of the work for
+making modifications to it. "Object code" means any non-source form of
+a work.
+
+A "Standard Interface" means an interface that either is an official
+standard defined by a recognized standards body, or, in the case of
+interfaces specified for a particular programming language, one that
+is widely used among developers working in that language.
+
+The "System Libraries" of an executable work include anything, other
+than the work as a whole, that (a) is included in the normal form of
+packaging a Major Component, but which is not part of that Major
+Component, and (b) serves only to enable use of the work with that
+Major Component, or to implement a Standard Interface for which an
+implementation is available to the public in source code form. A
+"Major Component", in this context, means a major essential component
+(kernel, window system, and so on) of the specific operating system
+(if any) on which the executable work runs, or a compiler used to
+produce the work, or an object code interpreter used to run it.
+
+The "Corresponding Source" for a work in object code form means all
+the source code needed to generate, install, and (for an executable
+work) run the object code and to modify the work, including scripts to
+control those activities. However, it does not include the work's
+System Libraries, or general-purpose tools or generally available free
+programs which are used unmodified in performing those activities but
+which are not part of the work. For example, Corresponding Source
+includes interface definition files associated with source files for
+the work, and the source code for shared libraries and dynamically
+linked subprograms that the work is specifically designed to require,
+such as by intimate data communication or control flow between those
+subprograms and other parts of the work.
+
+The Corresponding Source need not include anything that users can
+regenerate automatically from other parts of the Corresponding Source.
+
+The Corresponding Source for a work in source code form is that same
+work.
+
+#### 2. Basic Permissions.
+
+All rights granted under this License are granted for the term of
+copyright on the Program, and are irrevocable provided the stated
+conditions are met. This License explicitly affirms your unlimited
+permission to run the unmodified Program. The output from running a
+covered work is covered by this License only if the output, given its
+content, constitutes a covered work. This License acknowledges your
+rights of fair use or other equivalent, as provided by copyright law.
+
+You may make, run and propagate covered works that you do not convey,
+without conditions so long as your license otherwise remains in force.
+You may convey covered works to others for the sole purpose of having
+them make modifications exclusively for you, or provide you with
+facilities for running those works, provided that you comply with the
+terms of this License in conveying all material for which you do not
+control copyright. Those thus making or running the covered works for
+you must do so exclusively on your behalf, under your direction and
+control, on terms that prohibit them from making any copies of your
+copyrighted material outside their relationship with you.
+
+Conveying under any other circumstances is permitted solely under the
+conditions stated below. Sublicensing is not allowed; section 10 makes
+it unnecessary.
+
+#### 3. Protecting Users' Legal Rights From Anti-Circumvention Law.
+
+No covered work shall be deemed part of an effective technological
+measure under any applicable law fulfilling obligations under article
+11 of the WIPO copyright treaty adopted on 20 December 1996, or
+similar laws prohibiting or restricting circumvention of such
+measures.
+
+When you convey a covered work, you waive any legal power to forbid
+circumvention of technological measures to the extent such
+circumvention is effected by exercising rights under this License with
+respect to the covered work, and you disclaim any intention to limit
+operation or modification of the work as a means of enforcing, against
+the work's users, your or third parties' legal rights to forbid
+circumvention of technological measures.
+
+#### 4. Conveying Verbatim Copies.
+
+You may convey verbatim copies of the Program's source code as you
+receive it, in any medium, provided that you conspicuously and
+appropriately publish on each copy an appropriate copyright notice;
+keep intact all notices stating that this License and any
+non-permissive terms added in accord with section 7 apply to the code;
+keep intact all notices of the absence of any warranty; and give all
+recipients a copy of this License along with the Program.
+
+You may charge any price or no price for each copy that you convey,
+and you may offer support or warranty protection for a fee.
+
+#### 5. Conveying Modified Source Versions.
+
+You may convey a work based on the Program, or the modifications to
+produce it from the Program, in the form of source code under the
+terms of section 4, provided that you also meet all of these
+conditions:
+
+-   a) The work must carry prominent notices stating that you modified
+    it, and giving a relevant date.
+-   b) The work must carry prominent notices stating that it is
+    released under this License and any conditions added under
+    section 7. This requirement modifies the requirement in section 4
+    to "keep intact all notices".
+-   c) You must license the entire work, as a whole, under this
+    License to anyone who comes into possession of a copy. This
+    License will therefore apply, along with any applicable section 7
+    additional terms, to the whole of the work, and all its parts,
+    regardless of how they are packaged. This License gives no
+    permission to license the work in any other way, but it does not
+    invalidate such permission if you have separately received it.
+-   d) If the work has interactive user interfaces, each must display
+    Appropriate Legal Notices; however, if the Program has interactive
+    interfaces that do not display Appropriate Legal Notices, your
+    work need not make them do so.
+
+A compilation of a covered work with other separate and independent
+works, which are not by their nature extensions of the covered work,
+and which are not combined with it such as to form a larger program,
+in or on a volume of a storage or distribution medium, is called an
+"aggregate" if the compilation and its resulting copyright are not
+used to limit the access or legal rights of the compilation's users
+beyond what the individual works permit. Inclusion of a covered work
+in an aggregate does not cause this License to apply to the other
+parts of the aggregate.
+
+#### 6. Conveying Non-Source Forms.
+
+You may convey a covered work in object code form under the terms of
+sections 4 and 5, provided that you also convey the machine-readable
+Corresponding Source under the terms of this License, in one of these
+ways:
+
+-   a) Convey the object code in, or embodied in, a physical product
+    (including a physical distribution medium), accompanied by the
+    Corresponding Source fixed on a durable physical medium
+    customarily used for software interchange.
+-   b) Convey the object code in, or embodied in, a physical product
+    (including a physical distribution medium), accompanied by a
+    written offer, valid for at least three years and valid for as
+    long as you offer spare parts or customer support for that product
+    model, to give anyone who possesses the object code either (1) a
+    copy of the Corresponding Source for all the software in the
+    product that is covered by this License, on a durable physical
+    medium customarily used for software interchange, for a price no
+    more than your reasonable cost of physically performing this
+    conveying of source, or (2) access to copy the Corresponding
+    Source from a network server at no charge.
+-   c) Convey individual copies of the object code with a copy of the
+    written offer to provide the Corresponding Source. This
+    alternative is allowed only occasionally and noncommercially, and
+    only if you received the object code with such an offer, in accord
+    with subsection 6b.
+-   d) Convey the object code by offering access from a designated
+    place (gratis or for a charge), and offer equivalent access to the
+    Corresponding Source in the same way through the same place at no
+    further charge. You need not require recipients to copy the
+    Corresponding Source along with the object code. If the place to
+    copy the object code is a network server, the Corresponding Source
+    may be on a different server (operated by you or a third party)
+    that supports equivalent copying facilities, provided you maintain
+    clear directions next to the object code saying where to find the
+    Corresponding Source. Regardless of what server hosts the
+    Corresponding Source, you remain obligated to ensure that it is
+    available for as long as needed to satisfy these requirements.
+-   e) Convey the object code using peer-to-peer transmission,
+    provided you inform other peers where the object code and
+    Corresponding Source of the work are being offered to the general
+    public at no charge under subsection 6d.
+
+A separable portion of the object code, whose source code is excluded
+from the Corresponding Source as a System Library, need not be
+included in conveying the object code work.
+
+A "User Product" is either (1) a "consumer product", which means any
+tangible personal property which is normally used for personal,
+family, or household purposes, or (2) anything designed or sold for
+incorporation into a dwelling. In determining whether a product is a
+consumer product, doubtful cases shall be resolved in favor of
+coverage. For a particular product received by a particular user,
+"normally used" refers to a typical or common use of that class of
+product, regardless of the status of the particular user or of the way
+in which the particular user actually uses, or expects or is expected
+to use, the product. A product is a consumer product regardless of
+whether the product has substantial commercial, industrial or
+non-consumer uses, unless such uses represent the only significant
+mode of use of the product.
+
+"Installation Information" for a User Product means any methods,
+procedures, authorization keys, or other information required to
+install and execute modified versions of a covered work in that User
+Product from a modified version of its Corresponding Source. The
+information must suffice to ensure that the continued functioning of
+the modified object code is in no case prevented or interfered with
+solely because modification has been made.
+
+If you convey an object code work under this section in, or with, or
+specifically for use in, a User Product, and the conveying occurs as
+part of a transaction in which the right of possession and use of the
+User Product is transferred to the recipient in perpetuity or for a
+fixed term (regardless of how the transaction is characterized), the
+Corresponding Source conveyed under this section must be accompanied
+by the Installation Information. But this requirement does not apply
+if neither you nor any third party retains the ability to install
+modified object code on the User Product (for example, the work has
+been installed in ROM).
+
+The requirement to provide Installation Information does not include a
+requirement to continue to provide support service, warranty, or
+updates for a work that has been modified or installed by the
+recipient, or for the User Product in which it has been modified or
+installed. Access to a network may be denied when the modification
+itself materially and adversely affects the operation of the network
+or violates the rules and protocols for communication across the
+network.
+
+Corresponding Source conveyed, and Installation Information provided,
+in accord with this section must be in a format that is publicly
+documented (and with an implementation available to the public in
+source code form), and must require no special password or key for
+unpacking, reading or copying.
+
+#### 7. Additional Terms.
+
+"Additional permissions" are terms that supplement the terms of this
+License by making exceptions from one or more of its conditions.
+Additional permissions that are applicable to the entire Program shall
+be treated as though they were included in this License, to the extent
+that they are valid under applicable law. If additional permissions
+apply only to part of the Program, that part may be used separately
+under those permissions, but the entire Program remains governed by
+this License without regard to the additional permissions.
+
+When you convey a copy of a covered work, you may at your option
+remove any additional permissions from that copy, or from any part of
+it. (Additional permissions may be written to require their own
+removal in certain cases when you modify the work.) You may place
+additional permissions on material, added by you to a covered work,
+for which you have or can give appropriate copyright permission.
+
+Notwithstanding any other provision of this License, for material you
+add to a covered work, you may (if authorized by the copyright holders
+of that material) supplement the terms of this License with terms:
+
+-   a) Disclaiming warranty or limiting liability differently from the
+    terms of sections 15 and 16 of this License; or
+-   b) Requiring preservation of specified reasonable legal notices or
+    author attributions in that material or in the Appropriate Legal
+    Notices displayed by works containing it; or
+-   c) Prohibiting misrepresentation of the origin of that material,
+    or requiring that modified versions of such material be marked in
+    reasonable ways as different from the original version; or
+-   d) Limiting the use for publicity purposes of names of licensors
+    or authors of the material; or
+-   e) Declining to grant rights under trademark law for use of some
+    trade names, trademarks, or service marks; or
+-   f) Requiring indemnification of licensors and authors of that
+    material by anyone who conveys the material (or modified versions
+    of it) with contractual assumptions of liability to the recipient,
+    for any liability that these contractual assumptions directly
+    impose on those licensors and authors.
+
+All other non-permissive additional terms are considered "further
+restrictions" within the meaning of section 10. If the Program as you
+received it, or any part of it, contains a notice stating that it is
+governed by this License along with a term that is a further
+restriction, you may remove that term. If a license document contains
+a further restriction but permits relicensing or conveying under this
+License, you may add to a covered work material governed by the terms
+of that license document, provided that the further restriction does
+not survive such relicensing or conveying.
+
+If you add terms to a covered work in accord with this section, you
+must place, in the relevant source files, a statement of the
+additional terms that apply to those files, or a notice indicating
+where to find the applicable terms.
+
+Additional terms, permissive or non-permissive, may be stated in the
+form of a separately written license, or stated as exceptions; the
+above requirements apply either way.
+
+#### 8. Termination.
+
+You may not propagate or modify a covered work except as expressly
+provided under this License. Any attempt otherwise to propagate or
+modify it is void, and will automatically terminate your rights under
+this License (including any patent licenses granted under the third
+paragraph of section 11).
+
+However, if you cease all violation of this License, then your license
+from a particular copyright holder is reinstated (a) provisionally,
+unless and until the copyright holder explicitly and finally
+terminates your license, and (b) permanently, if the copyright holder
+fails to notify you of the violation by some reasonable means prior to
+60 days after the cessation.
+
+Moreover, your license from a particular copyright holder is
+reinstated permanently if the copyright holder notifies you of the
+violation by some reasonable means, this is the first time you have
+received notice of violation of this License (for any work) from that
+copyright holder, and you cure the violation prior to 30 days after
+your receipt of the notice.
+
+Termination of your rights under this section does not terminate the
+licenses of parties who have received copies or rights from you under
+this License. If your rights have been terminated and not permanently
+reinstated, you do not qualify to receive new licenses for the same
+material under section 10.
+
+#### 9. Acceptance Not Required for Having Copies.
+
+You are not required to accept this License in order to receive or run
+a copy of the Program. Ancillary propagation of a covered work
+occurring solely as a consequence of using peer-to-peer transmission
+to receive a copy likewise does not require acceptance. However,
+nothing other than this License grants you permission to propagate or
+modify any covered work. These actions infringe copyright if you do
+not accept this License. Therefore, by modifying or propagating a
+covered work, you indicate your acceptance of this License to do so.
+
+#### 10. Automatic Licensing of Downstream Recipients.
+
+Each time you convey a covered work, the recipient automatically
+receives a license from the original licensors, to run, modify and
+propagate that work, subject to this License. You are not responsible
+for enforcing compliance by third parties with this License.
+
+An "entity transaction" is a transaction transferring control of an
+organization, or substantially all assets of one, or subdividing an
+organization, or merging organizations. If propagation of a covered
+work results from an entity transaction, each party to that
+transaction who receives a copy of the work also receives whatever
+licenses to the work the party's predecessor in interest had or could
+give under the previous paragraph, plus a right to possession of the
+Corresponding Source of the work from the predecessor in interest, if
+the predecessor has it or can get it with reasonable efforts.
+
+You may not impose any further restrictions on the exercise of the
+rights granted or affirmed under this License. For example, you may
+not impose a license fee, royalty, or other charge for exercise of
+rights granted under this License, and you may not initiate litigation
+(including a cross-claim or counterclaim in a lawsuit) alleging that
+any patent claim is infringed by making, using, selling, offering for
+sale, or importing the Program or any portion of it.
+
+#### 11. Patents.
+
+A "contributor" is a copyright holder who authorizes use under this
+License of the Program or a work on which the Program is based. The
+work thus licensed is called the contributor's "contributor version".
+
+A contributor's "essential patent claims" are all patent claims owned
+or controlled by the contributor, whether already acquired or
+hereafter acquired, that would be infringed by some manner, permitted
+by this License, of making, using, or selling its contributor version,
+but do not include claims that would be infringed only as a
+consequence of further modification of the contributor version. For
+purposes of this definition, "control" includes the right to grant
+patent sublicenses in a manner consistent with the requirements of
+this License.
+
+Each contributor grants you a non-exclusive, worldwide, royalty-free
+patent license under the contributor's essential patent claims, to
+make, use, sell, offer for sale, import and otherwise run, modify and
+propagate the contents of its contributor version.
+
+In the following three paragraphs, a "patent license" is any express
+agreement or commitment, however denominated, not to enforce a patent
+(such as an express permission to practice a patent or covenant not to
+sue for patent infringement). To "grant" such a patent license to a
+party means to make such an agreement or commitment not to enforce a
+patent against the party.
+
+If you convey a covered work, knowingly relying on a patent license,
+and the Corresponding Source of the work is not available for anyone
+to copy, free of charge and under the terms of this License, through a
+publicly available network server or other readily accessible means,
+then you must either (1) cause the Corresponding Source to be so
+available, or (2) arrange to deprive yourself of the benefit of the
+patent license for this particular work, or (3) arrange, in a manner
+consistent with the requirements of this License, to extend the patent
+license to downstream recipients. "Knowingly relying" means you have
+actual knowledge that, but for the patent license, your conveying the
+covered work in a country, or your recipient's use of the covered work
+in a country, would infringe one or more identifiable patents in that
+country that you have reason to believe are valid.
+
+If, pursuant to or in connection with a single transaction or
+arrangement, you convey, or propagate by procuring conveyance of, a
+covered work, and grant a patent license to some of the parties
+receiving the covered work authorizing them to use, propagate, modify
+or convey a specific copy of the covered work, then the patent license
+you grant is automatically extended to all recipients of the covered
+work and works based on it.
+
+A patent license is "discriminatory" if it does not include within the
+scope of its coverage, prohibits the exercise of, or is conditioned on
+the non-exercise of one or more of the rights that are specifically
+granted under this License. You may not convey a covered work if you
+are a party to an arrangement with a third party that is in the
+business of distributing software, under which you make payment to the
+third party based on the extent of your activity of conveying the
+work, and under which the third party grants, to any of the parties
+who would receive the covered work from you, a discriminatory patent
+license (a) in connection with copies of the covered work conveyed by
+you (or copies made from those copies), or (b) primarily for and in
+connection with specific products or compilations that contain the
+covered work, unless you entered into that arrangement, or that patent
+license was granted, prior to 28 March 2007.
+
+Nothing in this License shall be construed as excluding or limiting
+any implied license or other defenses to infringement that may
+otherwise be available to you under applicable patent law.
+
+#### 12. No Surrender of Others' Freedom.
+
+If conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
+excuse you from the conditions of this License. If you cannot convey a
+covered work so as to satisfy simultaneously your obligations under
+this License and any other pertinent obligations, then as a
+consequence you may not convey it at all. For example, if you agree to
+terms that obligate you to collect a royalty for further conveying
+from those to whom you convey the Program, the only way you could
+satisfy both those terms and this License would be to refrain entirely
+from conveying the Program.
+
+#### 13. Use with the GNU Affero General Public License.
+
+Notwithstanding any other provision of this License, you have
+permission to link or combine any covered work with a work licensed
+under version 3 of the GNU Affero General Public License into a single
+combined work, and to convey the resulting work. The terms of this
+License will continue to apply to the part which is the covered work,
+but the special requirements of the GNU Affero General Public License,
+section 13, concerning interaction through a network will apply to the
+combination as such.
+
+#### 14. Revised Versions of this License.
+
+The Free Software Foundation may publish revised and/or new versions
+of the GNU General Public License from time to time. Such new versions
+will be similar in spirit to the present version, but may differ in
+detail to address new problems or concerns.
+
+Each version is given a distinguishing version number. If the Program
+specifies that a certain numbered version of the GNU General Public
+License "or any later version" applies to it, you have the option of
+following the terms and conditions either of that numbered version or
+of any later version published by the Free Software Foundation. If the
+Program does not specify a version number of the GNU General Public
+License, you may choose any version ever published by the Free
+Software Foundation.
+
+If the Program specifies that a proxy can decide which future versions
+of the GNU General Public License can be used, that proxy's public
+statement of acceptance of a version permanently authorizes you to
+choose that version for the Program.
+
+Later license versions may give you additional or different
+permissions. However, no additional obligations are imposed on any
+author or copyright holder as a result of your choosing to follow a
+later version.
+
+#### 15. Disclaimer of Warranty.
+
+THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY
+APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT
+HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT
+WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT
+LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+A PARTICULAR PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND
+PERFORMANCE OF THE PROGRAM IS WITH YOU. SHOULD THE PROGRAM PROVE
+DEFECTIVE, YOU ASSUME THE COST OF ALL NECESSARY SERVICING, REPAIR OR
+CORRECTION.
+
+#### 16. Limitation of Liability.
+
+IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING
+WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES AND/OR
+CONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
+INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES
+ARISING OUT OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT
+NOT LIMITED TO LOSS OF DATA OR DATA BEING RENDERED INACCURATE OR
+LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A FAILURE OF THE PROGRAM
+TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF SUCH HOLDER OR OTHER
+PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.
+
+#### 17. Interpretation of Sections 15 and 16.
+
+If the disclaimer of warranty and limitation of liability provided
+above cannot be given local legal effect according to their terms,
+reviewing courts shall apply local law that most closely approximates
+an absolute waiver of all civil liability in connection with the
+Program, unless a warranty or assumption of liability accompanies a
+copy of the Program in return for a fee.
+
+END OF TERMS AND CONDITIONS
+
+### How to Apply These Terms to Your New Programs
+
+If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these
+terms.
+
+To do so, attach the following notices to the program. It is safest to
+attach them to the start of each source file to most effectively state
+the exclusion of warranty; and each file should have at least the
+"copyright" line and a pointer to where the full notice is found.
+
+        <one line to give the program's name and a brief idea of what it does.>
+        Copyright (C) <year>  <name of author>
+
+        This program is free software: you can redistribute it and/or modify
+        it under the terms of the GNU General Public License as published by
+        the Free Software Foundation, either version 3 of the License, or
+        (at your option) any later version.
+
+        This program is distributed in the hope that it will be useful,
+        but WITHOUT ANY WARRANTY; without even the implied warranty of
+        MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+        GNU General Public License for more details.
+
+        You should have received a copy of the GNU General Public License
+        along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+Also add information on how to contact you by electronic and paper
+mail.
+
+If the program does terminal interaction, make it output a short
+notice like this when it starts in an interactive mode:
+
+        <program>  Copyright (C) <year>  <name of author>
+        This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+        This is free software, and you are welcome to redistribute it
+        under certain conditions; type `show c' for details.
+
+The hypothetical commands \`show w' and \`show c' should show the
+appropriate parts of the General Public License. Of course, your
+program's commands might be different; for a GUI interface, you would
+use an "about box".
+
+You should also get your employer (if you work as a programmer) or
+school, if any, to sign a "copyright disclaimer" for the program, if
+necessary. For more information on this, and how to apply and follow
+the GNU GPL, see <http://www.gnu.org/licenses/>.
+
+The GNU General Public License does not permit incorporating your
+program into proprietary programs. If your program is a subroutine
+library, you may consider it more useful to permit linking proprietary
+applications with the library. If this is what you want to do, use the
+GNU Lesser General Public License instead of this License. But first,
+please read <http://www.gnu.org/philosophy/why-not-lgpl.html>.
\ No newline at end of file
diff --git a/Master/texmf-dist/doc/latex/invoice2/README.md b/Master/texmf-dist/doc/latex/invoice2/README.md
new file mode 100644
index 00000000000..d5a4c26b440
--- /dev/null
+++ b/Master/texmf-dist/doc/latex/invoice2/README.md
@@ -0,0 +1,44 @@
+# invoice2 – Intelligent invoices with LaTeX3
+
+## What is it?
+
+While there already are several solutions for LaTeX invoices, most are either
+sum-it-yourself templates and the [invoice](https://www.ctan.org/pkg/invoice)
+package, which appears to be unmaintained and fails to work for my documents,
+sespecially documents using KOMA-Script. Since LaTeX3 offers a comfortable
+interface for working with caculations, this package (re-)implements invoice
+functionalioty using LaTeX3.
+
+## Building the package
+
+invoice2 uses the [l3build](https://www.ctan.org/pkg/l3build) tool to create
+the package and documentation files. If your LaTeX distribution is sufficiently
+up to date, execute
+
+> ./build.lua ctan
+
+in a source checkout to build a CTAN upload zip and a TDS zip. If you just want
+to install a copy of invoice2, execute
+
+> ./build.lua install
+
+to copy the package to your texmf tree.
+
+After building, consult the invoice2.pdf for the actual package documentation.
+
+## Copyright and Licensing
+
+Copyright (C) 2017 Simon Dierl <simon.dierl@cs.tu-dortmund.de>
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
diff --git a/Master/texmf-dist/doc/latex/invoice2/README.txt b/Master/texmf-dist/doc/latex/invoice2/README.txt
new file mode 100644
index 00000000000..e69de29bb2d
--- /dev/null
+++ b/Master/texmf-dist/doc/latex/invoice2/README.txt
diff --git a/Master/texmf-dist/doc/latex/invoice2/invoice2-english.trsl b/Master/texmf-dist/doc/latex/invoice2/invoice2-english.trsl
new file mode 100644
index 00000000000..11385933d30
--- /dev/null
+++ b/Master/texmf-dist/doc/latex/invoice2/invoice2-english.trsl
@@ -0,0 +1,37 @@
+%%
+%% This is file `invoice2-english.trsl',
+%% generated with the docstrip utility.
+%%
+%% The original source files were:
+%%
+%% invoice2.dtx  (with options: `dictEnglish')
+%% 
+%% Copyright (C) 2017 Simon Dierl
+%% 
+%% This program is free software: you can redistribute it and/or modify
+%% it under the terms of the GNU General Public License as published by
+%% the Free Software Foundation, either version 3 of the License, or
+%% (at your option) any later version.
+%% 
+%% This program is distributed in the hope that it will be useful,
+%% but WITHOUT ANY WARRANTY; without even the implied warranty of
+%% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+%% GNU General Public License for more details.
+%% 
+%% You should have received a copy of the GNU General Public License
+%% along with this program.  If not, see <http://www.gnu.org/licenses/>.
+%% 
+\ProvideDictionaryFor{English}{invoice2}
+\ProvideDictTranslation{invoice2-thousands-sep}{\,}
+\ProvideDictTranslation{invoice2-decimal-point}{.}
+\ProvideDictTranslation{invoice2-amount}{Amount}
+\ProvideDictTranslation{invoice2-item}{Item}
+\ProvideDictTranslation{invoice2-vat}{VAT}
+\ProvideDictTranslation{invoice2-unit-price}{Unit~Price}
+\ProvideDictTranslation{invoice2-price}{Price}
+\ProvideDictTranslation{invoice2-net-total}{Net~Total}
+\ProvideDictTranslation{invoice2-vat-total}{VAT}
+\ProvideDictTranslation{invoice2-gross-total}{Gross~Total}
+%% 
+%%
+%% End of file `invoice2-english.trsl'.
diff --git a/Master/texmf-dist/doc/latex/invoice2/invoice2-german.trsl b/Master/texmf-dist/doc/latex/invoice2/invoice2-german.trsl
new file mode 100644
index 00000000000..e81393aae8b
--- /dev/null
+++ b/Master/texmf-dist/doc/latex/invoice2/invoice2-german.trsl
@@ -0,0 +1,37 @@
+%%
+%% This is file `invoice2-german.trsl',
+%% generated with the docstrip utility.
+%%
+%% The original source files were:
+%%
+%% invoice2.dtx  (with options: `dictGerman')
+%% 
+%% Copyright (C) 2017 Simon Dierl
+%% 
+%% This program is free software: you can redistribute it and/or modify
+%% it under the terms of the GNU General Public License as published by
+%% the Free Software Foundation, either version 3 of the License, or
+%% (at your option) any later version.
+%% 
+%% This program is distributed in the hope that it will be useful,
+%% but WITHOUT ANY WARRANTY; without even the implied warranty of
+%% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+%% GNU General Public License for more details.
+%% 
+%% You should have received a copy of the GNU General Public License
+%% along with this program.  If not, see <http://www.gnu.org/licenses/>.
+%% 
+\ProvideDictionaryFor{German}{invoice2}
+\ProvideDictTranslation{invoice2-thousands-sep}{\,}
+\ProvideDictTranslation{invoice2-decimal-point}{,}
+\ProvideDictTranslation{invoice2-amount}{Anzahl}
+\ProvideDictTranslation{invoice2-item}{Posten}
+\ProvideDictTranslation{invoice2-vat}{MwSt.}
+\ProvideDictTranslation{invoice2-unit-price}{St\"uckpreis}
+\ProvideDictTranslation{invoice2-price}{Preis}
+\ProvideDictTranslation{invoice2-net-total}{Nettobetrag}
+\ProvideDictTranslation{invoice2-vat-total}{MwSt.}
+\ProvideDictTranslation{invoice2-gross-total}{Gesamtbetrag}
+%% 
+%%
+%% End of file `invoice2-german.trsl'.
diff --git a/Master/texmf-dist/doc/latex/invoice2/invoice2.pdf b/Master/texmf-dist/doc/latex/invoice2/invoice2.pdf
new file mode 100644
index 00000000000..fbf336c867d
--- /dev/null
+++ b/Master/texmf-dist/doc/latex/invoice2/invoice2.pdf
diff --git a/Master/texmf-dist/source/latex/invoice2/invoice2.dtx b/Master/texmf-dist/source/latex/invoice2/invoice2.dtx
new file mode 100644
index 00000000000..a69bab127e0
--- /dev/null
+++ b/Master/texmf-dist/source/latex/invoice2/invoice2.dtx
@@ -0,0 +1,1066 @@
+% \iffalse meta-comment
+%
+% File: invoice2.dtx Copyright (C) 2017 Simon Dierl
+%
+% This program is free software: you can redistribute it and/or modify
+% it under the terms of the GNU General Public License as published by
+% the Free Software Foundation, either version 3 of the License, or
+% (at your option) any later version.
+% 
+% This program is distributed in the hope that it will be useful,
+% but WITHOUT ANY WARRANTY; without even the implied warranty of
+% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+% GNU General Public License for more details.
+%
+% You should have received a copy of the GNU General Public License
+% along with this program.  If not, see <http://www.gnu.org/licenses/>.
+%
+% \fi
+%
+% \iffalse
+%<*driver>
+\documentclass[full,lm-default]{l3doc}
+\usepackage[T1]{fontenc}
+\usepackage[utf8]{inputenc}
+
+\usepackage{amsmath}
+\usepackage{amsfonts}
+\usepackage[USenglish]{babel}
+\usepackage{csquotes}
+\usepackage[useregional,showdow]{datetime2}
+\usepackage{enumitem}
+\usepackage{eurosym}
+\usepackage{invoice2}
+
+\hypersetup{hidelinks}
+
+\begin{document}
+    \DocInput{\jobname.dtx}
+\end{document}
+%</driver>
+% \fi
+%
+% \title{The \pkg{invoice2} package\\
+%    Intelligent invoices with \LaTeX{}3}
+%
+% \author{Simon Dierl
+%   \texttt{\href{mailto:simon.dierl@cs.tu-dortmund.de}
+%       {<simon.dierl@cs.tu-dortmund.de>}}\\[.25\baselineskip]
+%	\url{https://github.com/no-preserve-root/invoice2}}
+%
+% \date{Version 1.0\\[.25\baselineskip]\DTMDate{2017-7-15}}
+%
+% \maketitle
+%
+% \begin{documentation}
+%
+% While there exists a vast amount of templates, unpublished packages and code
+% snippets designed for creating invoices, the only solution available in the
+% CTAN is the \pkg{invoice}\footnote{\url{https://www.ctan.org/pkg/invoice}}
+% package, which is not actively maintained and lacks
+% e.\,g.~internationalization support while requiring use of a project
+% structure that does not fit many use cases.
+%
+% Thus, this package aims to reimplement the functionality provided by
+% \pkg{invoice} using \LaTeX3, while using the print-friendly layout provided
+% by the \pkg{booktabs}\footnote{\url{https://www.ctan.org/pkg/booktabs}}
+% package.
+%
+% \tableofcontents
+%
+% \part{User documentation}
+%
+% \section{Package Configuration}
+%
+% \pkg{invoice2} offers extensive options for customization. Most of these
+% options are not likely to change in the middle of a document; these shold be
+% passed as package options. However, for maximum flexibility, the global
+% options can be changed at run time or overridden per \cmd{invoice}
+% environment.
+%
+% The options supported by this package are:
+% \begin{description}
+%    \item[vat] Controls the global default for VAT. VAT can be overridden per
+%        invoice item and is either automatically added or subtracted (see the
+%        next parameter for details). This is given as a floating point number,
+%        e.\,g.~.19 for 19\,\%. Default is 0\,\%.
+%    \item[included-vat] Controls if prices are provided with VAT included or
+%        excluded. If VAT is included, all prices are gross prices, the VAT is
+%        subtracted to show the net price. If VAT is excluded, all prices are
+%        net prices, the VAT is added to show the gross price. Default is
+%        excluded VAT.
+%    \item[currency-symbol] The currency symbol to use, e.g. \euro{}. 
+%        Default is \$.
+%    \item[currency-fraction-digits] The fractional digits to use for the 
+%        currency. For almost all currencies, this is two (100 of the smaller
+%        unit make 1 of the larger). Default is 2.
+%    \item[colorize] Enables colorization. While the typographical results may
+%        be mixed, colorization can help read very long invoices. Default is
+%        off.
+%    \item[odd-color] The color to use for odd invoice rows, if colorization is
+%        enabled. The color must be understood by \pkg{xcolor}. Default is
+%        white.
+%    \item[even-color] The color to use for even invoice rows, if colorization 
+%        is enabled. The color must be understood by \pkg{xcolor}. Default is
+%        light grey (lightgray).
+%    \item[title-color] The color to use for the title row, if colorization is
+%        enabled. The color must be understood by \pkg{xcolor}. Default is
+%        white.
+%    \item[total-color] The color to use for total rows, if colorization is
+%        enabled. The color must be understood by \pkg{xcolor}. Default is
+%        white.
+%\end{description}
+%
+% \section{Localization}
+%
+% Internationalization for this package is provided by the
+% \pkg{translations}\footnote{\url{https://www.ctan.org/pkg/translations}}
+% package. \pkg{translations} uses a key-to-translation mapping that can be
+% overridden by the user. See the package documentation for further information.
+%
+% At the moment, localizations for english and german are provided. See the
+% documentation for the \pkg{translations} package for adding new localizations.
+% Please consider contributing your translations to this project.
+% 
+% The following keys are defined:
+% \begin{description}
+%    \item[invoice2-thousands-sep] The separator between thousands, e.\,g. the
+%        space in 1\,000. Default is a small space.
+%    \item[invoice2-decimal-point] The separator between whole and 
+%        fractional parts, e.\,g.~the dot in 40.00. Default is a dot.
+%    \item[invoice2-amount] The \enquote{Amount} column title.
+%    \item[invoice2-item] The \enquote{Item} column title.
+%    \item[invoice2-vat] The \enquote{VAT} column title.
+%    \item[invoice2-unit-price] The \enquote{Unit Price} column title.
+%    \item[invoice2-price] The \enquote{Price} column title.
+%    \item[invoice2-net-total] The \enquote{Net Total} row label.
+%    \item[invoice2-vat-total] The \enquote{VAT} row label.
+%    \item[invoice2-gross-total] The \enquote{Gross Total} row label.
+%\end{description}
+%
+% \begin{function}{\invoiceoptions}
+% \begin{syntax}
+% \cs{invoiceoptions} \marg{key=value…}
+% \end{syntax}
+% All of the package options can be changed in the document by using this
+% command. The syntax is identical to the package options.
+% \end{function}
+%
+% \section{Typesetting invoices}
+%
+% An invoice is typeset as a table having between two and five columns. Each row
+% will correspond to an item in the invoice. A row \emph{always} has an item
+% name and a price. If \emph{any} item in the invoice hat a VAT that is not
+% 0\,\%, \emph{every} row will list its VAT. Also, if \emph{any} item has an
+% amount that is not one, \emph{every} row will list both price per unit and
+% the amount.
+%
+% If an item hat non-zero VAT, the net and gross totals will also differ. In
+% this case, the package will compute the net total, the total VAT and the
+% gross total and denote them below the invoice. If all items have 0\,\%-VAT,
+% only a gross total will be given.
+%
+% \begin{function}{\begin{invoice}, \end{invoice}}
+% \begin{syntax}
+% \cs{begin} \oarg{key=value…} \{invoice\}
+% \cs{end} \{invoice\}
+% \end{syntax}
+% Invoices are enclosed in \cmd{invoice} environments. These environments can
+% not be nested. Each environment can override the package settings by means of
+% its optional arguments. The overridden arguments only apply to the current
+% invoice.
+%
+% Inside the environment, \emph{only} \cmd{\invoiceitem} and
+% \cmd{\invoicesingleitem} commands may be safely used.
+% \end{function}
+%
+% \begin{function}{\invoiceitem, \invoicesingleitem}
+% \begin{syntax}
+% \cs{invoiceitem} \oarg{VAT} \marg{amount} \marg{item name} \marg{unit price}
+% \cs{invoicesingleitem} \oarg{VAT} \marg{item name} \marg{unit price}
+% \end{syntax}
+% These commands add an item to the current invoice. The VAT argument is
+% optional, if not given, VAT will default to the value set in the 
+% configuration. For singular items, the second form can be used to imply an
+% amount of 1.
+% 
+% VAT must be given as a floating point value (see the configuration parameter
+% list for details). The amount must be an integer, the unit price a floating
+% point number. Do \emph{not} add a currency symbol or formatting to the unit
+% price.
+% \end{function}
+%
+% \section{Examples}
+%
+% Let us begin with a simple invoice with single items and no VAT. The invoice
+% will only have two columns and a gross total. We do, however, change the
+% currency symbol to \euro{}. Since we only have single copies, we will use
+% the \cmd{\invoicesingleitem} command.
+%
+% \begin{verbatim}
+%    \begin{invoice}[currency-symbol={\euro{}}]
+%        \invoicesingleitem{Ignition!}{4087.99}
+%        \invoicesingleitem{The Art of Computer Programming 1--4}{162.99}
+%        \invoicesingleitem{The TeXbook}{55.69}
+%    \end{invoice}
+% \end{verbatim}
+% \begin{invoice}[currency-symbol={\euro{}}]
+%    \invoicesingleitem{Ignition!}{4087.99}
+%    \invoicesingleitem{The Art of Computer Programming 1--4}{162.99}
+%    \invoicesingleitem{The TeXbook}{55.69}
+% \end{invoice}
+%
+% A more complex example involves amounts and a VAT. We will apply a 9\,\% VAT
+% to our books and stock up on more copies of the TeXbook. This will enable
+% all columns and an extended total.
+%
+% \begin{verbatim}
+%    \invoiceoptions{vat=.09}
+%    \begin{invoice}[currency-symbol={\euro{}}]
+%        \invoicesingleitem{Ignition!}{4087.99}
+%        \invoicesingleitem{The Art of Computer Programming 1--4}{162.99}
+%        \invoiceitem{20}{The TeXbook}{55.69}
+%    \end{invoice}
+% \end{verbatim}
+% \invoiceoptions{vat=.09}
+% \begin{invoice}[currency-symbol={\euro{}}]
+%    \invoicesingleitem{Ignition!}{4087.99}
+%    \invoicesingleitem{The Art of Computer Programming 1--4}{162.99}
+%    \invoiceitem{20}{The TeXbook}{55.69}
+% \end{invoice}
+% \invoiceoptions{vat=0}
+%
+% Finally, let us toy with colorization. We wisely deceide to leave most
+% parts of the invoice white and only apply an extemely light grey to the even
+% rows.
+%
+% \begin{verbatim}
+%    \begin{invoice}[currency-symbol={\euro{}}, colorize,
+%        even-color={lightgray!50}]
+%        \invoicesingleitem{Ignition!}{4087.99}
+%        \invoicesingleitem{The Art of Computer Programming 1--4}{162.99}
+%        \invoicesingleitem{The TeXbook}{55.69}
+%    \end{invoice}
+% \end{verbatim}
+% \begin{invoice}[currency-symbol={\euro{}}, colorize,
+%    even-color={lightgray!50}]
+%    \invoicesingleitem{Ignition!}{4087.99}
+%    \invoicesingleitem{The Art of Computer Programming 1--4}{162.99}
+%    \invoicesingleitem{The TeXbook}{55.69}
+% \end{invoice}
+%
+% \section{Version History}
+%
+% \subsection{Version 1.0}
+%
+% \changes{1.0}{2017/07/15}{First public release}
+% \begin{itemize}[nosep]
+%    \item First public release.
+%    \item Support configuration via package options, \cmd{\invoiceoptions}
+%    command and environment options.
+%    \item Localization via \pkg{translations}.
+% \end{itemize}
+%
+% \section{License}
+% 
+% This program is free software: you can redistribute it and/or modify
+% it under the terms of the GNU General Public License as published by
+% the Free Software Foundation, either version 3 of the License, or
+% (at your option) any later version.
+% 
+% This program is distributed in the hope that it will be useful,
+% but WITHOUT ANY WARRANTY; without even the implied warranty of
+% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+% GNU General Public License for more details.
+% 
+% You should have received a copy of the GNU General Public License
+% along with this program.  If not, see \url{http://www.gnu.org/licenses/}.
+%
+% \end{documentation}
+%
+% \begin{implementation}
+%
+% \part{\pkg{invoice2} implementation}
+%
+%    \begin{macrocode}
+%<*package>
+%<@@=invoicetwo>
+%    \end{macrocode}
+%
+% \section{Setup and Initialization}
+%
+%    \begin{macrocode}
+\RequirePackage{booktabs}
+\RequirePackage{expl3}
+\RequirePackage{l3keys2e}
+\RequirePackage{longtable}
+\RequirePackage{siunitx}
+\RequirePackage{translations}
+\RequirePackage[table]{xcolor}
+\RequirePackage{xparse}
+\ProvidesExplPackage{invoice2}{2017/07/15}{1.0}
+    {Next-generation invoice typesetting with booktabs}
+%    \end{macrocode}
+%
+% Now, load our dictionary files and set fallback translations. We emit the
+% dictionaries in section \ref{sec:dictionaries}.
+%
+%    \begin{macrocode}
+\LoadDictionaryFor{english}{invoice2}
+\LoadDictionaryFor{german}{invoice2}
+\DeclareTranslationFallback{invoice2-thousands-sep}{\,}
+\DeclareTranslationFallback{invoice2-decimal-point}{.}
+\DeclareTranslationFallback{invoice2-amount}{Amount}
+\DeclareTranslationFallback{invoice2-item}{Item}
+\DeclareTranslationFallback{invoice2-vat}{VAT}
+\DeclareTranslationFallback{invoice2-unit-price}{Unit~Price}
+\DeclareTranslationFallback{invoice2-price}{Price}
+\DeclareTranslationFallback{invoice2-net-total}{Net~Total}
+\DeclareTranslationFallback{invoice2-vat-total}{VAT}
+\DeclareTranslationFallback{invoice2-gross-total}{Gross~Total}
+%    \end{macrocode}
+%
+% \section{Variables and Constants}
+%
+% All variables that control invoice typesetting can be set on
+% \begin{enumerate}[noitemsep, label=\alph*)]
+%    \item the package level, as a package option
+%    \item the package level, using the \cmd{invoiceoptions} command
+%    \item per \cmd{invoice} environment, via the same syntax
+%    \item per invoice line, for some options (e.\,g.~VAT).
+% \end{enumerate}
+%
+% \subsection{VAT Computation}
+%
+% \begin{variable}{\l_@@_vat_fp}
+% The default value for VAT. If an invoice has only zero VAT for all entries,
+% no VAT is added and the column is not rendered. VAT can be set per line.
+% 
+%    \begin{macrocode}
+\fp_new:N \l_@@_vat_fp
+%    \end{macrocode}
+% \end{variable}
+%
+% \begin{variable}{\l_@@_included_vat_bool}
+% Controls if VAT is already included into the given prices. If true, the
+% total will compute the net total and display it. If false, the total will
+% compute the gross total. If the VAT is zero, this does nothing. We will render
+% a gross total only.
+% 
+%    \begin{macrocode}
+\bool_new:N \l_@@_included_vat_bool
+%    \end{macrocode}
+% \end{variable}
+%
+% \begin{variable}{\l_@@_currency_symbol_tl}
+% The currency symbol to use.
+%
+% \subsection{Price Typesetting}
+% 
+%    \begin{macrocode}
+\tl_new:N \l_@@_currency_symbol_tl
+%    \end{macrocode}
+% \end{variable}
+%
+% \begin{variable}{\l_@@_currency_fraction_digits_int}
+% The number of fractional digits for the currency. Contrary to popular opinion,
+% this does not always equal two.
+% 
+%    \begin{macrocode}
+\int_new:N \l_@@_currency_fraction_digits_int
+%    \end{macrocode}
+% \end{variable}
+%
+% \subsection{Colorization}
+%
+% \begin{variable}{\l_@@_colorize_bool}
+% Controls if the invoice should be colorized at all. We only support
+% alternating colorization for even and odd lines and a special color for the
+% total line.
+% 
+%    \begin{macrocode}
+\bool_new:N \l_@@_colorize_bool
+%    \end{macrocode}
+% \end{variable}
+%
+% \begin{variable}{\l_@@_odd_color_tl}
+% The color for odd lines. Only used if colorization is enabled.
+% 
+%    \begin{macrocode}
+\tl_new:N \l_@@_odd_color_tl
+\tl_set:Nn \l_@@_odd_color_tl {white}
+%    \end{macrocode}
+% \end{variable}
+%
+% \begin{variable}{\l_@@_even_color_tl}
+% The color for even lines. Only used if colorization is enabled.
+% 
+%    \begin{macrocode}
+\tl_new:N \l_@@_even_color_tl
+\tl_set:Nn \l_@@_even_color_tl {lightgray}
+%    \end{macrocode}
+% \end{variable}
+%
+% \begin{variable}{\l_@@_title_color_tl}
+% The color for the title line. Only used if colorization is enabled.
+% 
+%    \begin{macrocode}
+\tl_new:N \l_@@_title_color_tl
+\tl_set:Nn \l_@@_title_color_tl {white}
+%    \end{macrocode}
+% \end{variable}
+%
+% \begin{variable}{\l_@@_total_color_tl}
+% The color for the total line. Only used if colorization is enabled.
+% 
+%    \begin{macrocode}
+\tl_new:N \l_@@_total_color_tl
+\tl_set:Nn \l_@@_total_color_tl {white}
+%    \end{macrocode}
+% \end{variable}
+%
+% \subsection{Internal State Tracking}
+%
+% \begin{variable}{\l_@@_in_invoice_bool}
+% Tracks if we are in an invoice environment. This allows us to crash when
+% nesting invoice environments by accident.
+% 
+%    \begin{macrocode}
+\bool_new:N \l_@@_in_invoice_bool
+%    \end{macrocode}
+% \end{variable}
+%
+% \begin{variable}{\l_@@_row_number_int}
+% Counts the invoice rows. We use this to tell even from odd lines. Starts with
+% 1; this must be reset at the beginning of each invoice.
+% 
+%    \begin{macrocode}
+\int_new:N \g_@@_row_number_int
+%    \end{macrocode}
+% \end{variable}
+%
+% \begin{variable}{\l_@@_vat_nonzero_bool}
+% Tracks if we have already encountered a line with non-zero VAT. If so, we
+% will render a VAT column and separate gross and net totals.
+% 
+%    \begin{macrocode}
+\bool_new:N \l_@@_vat_nonzero_bool
+%    \end{macrocode}
+% \end{variable}
+%
+% \begin{variable}{\l_@@_amount_nonone_bool}
+% Tracks if we have already encountered a line with non-one amount. If so, we
+% will render an amount and an unit price column.
+% 
+%    \begin{macrocode}
+\bool_new:N \l_@@_amount_nonone_bool
+%    \end{macrocode}
+% \end{variable}
+%
+% \begin{variable}{\l_@@_net_total_fp}
+% The running net total.
+% 
+%    \begin{macrocode}
+\fp_new:N \l_@@_net_total_fp
+%    \end{macrocode}
+% \end{variable}
+%
+% \begin{variable}{\l_@@_vat_total_fp}
+% The running VAT total.
+% 
+%    \begin{macrocode}
+\fp_new:N \l_@@_vat_total_fp
+%    \end{macrocode}
+% \end{variable}
+%
+% \begin{variable}{\l_@@_gross_total_fp}
+% The running gross total.
+% 
+%    \begin{macrocode}
+\fp_new:N \l_@@_gross_total_fp
+%    \end{macrocode}
+% \end{variable}
+%
+% \begin{variable}{\l_@@_tabular_tl}
+% The tabular under construction. We create the tabular contents on the fly,
+% using a conditional for the VAT column that is expanded only when emitting the
+% invoice.
+% 
+%    \begin{macrocode}
+\tl_new:N \l_@@_tabular_tl
+%    \end{macrocode}
+% \end{variable}
+%
+% \section{Configuration}
+%
+% We define a \pkg{l3keys} key list for the package. We will reuse this for all
+% configuration, except for item-specific VAT, which will override the global
+% VAT setting. We handle this in the corresponding function.
+%
+%    \begin{macrocode}
+\keys_define:nn {invoice2} {
+    vat .fp_set:N = \l_@@_vat_fp,
+    vat .value_required:n = true,
+    vat .initial:n = 0,
+    included-vat .bool_set:N = \l_@@_included_vat_bool,
+    included-vat .initial:n = false,
+    currency-symbol .tl_set:N = \l_@@_currency_symbol_tl,
+    currency-symbol .value_required:n = true,
+    currency-symbol .initial:n = {\$},
+    currency-fraction-digits .int_set:N = \l_@@_currency_fraction_digits_int,
+    currency-fraction-digits .value_required:n = true,
+    currency-fraction-digits .initial:n = 2,
+    colorize .bool_set:N = \l_@@_colorize_bool,
+    colorize .initial:n = false,
+    odd-color .initial:n = white,
+    odd-color .value_required:n = true,
+    odd-color .tl_set:N = \l_@@_odd_color_tl,
+    even-color .initial:n = lightgray,
+    even-color .value_required:n = true,
+    even-color .tl_set:N = \l_@@_even_color_tl,
+    title-color .initial:n = white,
+    title-color .value_required:n = true,
+    title-color .tl_set:N = \l_@@_title_color_tl,
+    total-color .initial:n = white,
+    total-color .value_required:n = true,
+    total-color .tl_set:N = \l_@@_total_color_tl
+}
+%    \end{macrocode}
+%
+% \subsection{Package Parameters}
+%
+% Fortunately, \pkg{l3keys2e} handles the heavy lifting for us.
+%
+%    \begin{macrocode}
+\ProcessKeysOptions{invoice2}
+%    \end{macrocode}
+%
+% \subsection{\cmd{invoiceoptions} Command}
+% 
+% \begin{macro}{\invoiceoptions}
+% We also provide an interface to change the configuration at run time.
+% 
+%    \begin{macrocode}
+\NewDocumentCommand{\invoiceoptions}{m}{
+    \keys_set:nn {invoice2} {#1}
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \section{The \cmd{invoice} Environment}
+%
+% \subsection{Header Rendering}
+%
+% \begin{macro}{\@@_print_column_specification:}
+% Emits the \cmd{\begin{longtable}}. The amount column is centered or skipped,
+% if all amounts are one. The item column is left-justified. The VAT column is
+% centered or skipped, if all VATs are zero. The unit price and price columns
+% are right-justified; unit price is skipped if amount is.
+%
+% Sind \pkg{longtable} refuses to expand the column specification, we force
+% prior expansion of the booleans.
+% 
+%    \begin{macrocode}
+\cs_new:Nn {\@@_print_begin_table:}{
+	\exp_args:Nx \longtable {
+		\bool_if:NT \l_@@_amount_nonone_bool { c }
+		l
+		\bool_if:NT \l_@@_vat_nonzero_bool { c }
+		r
+		\bool_if:NT \l_@@_amount_nonone_bool { r }
+	}
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\@@_print_column_title:n}
+% Emits a formatted column title.
+% 
+%    \begin{macrocode}
+\cs_new:Nn {\@@_print_column_title:n}{
+    \multicolumn{1}{c}{
+        \bool_if:NT \l_@@_colorize_bool {
+            \cellcolor{ \l_@@_title_color_tl }
+        }
+        \begin{scriptsize}
+            \textbf{#1}
+        \end{scriptsize}}
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\@@_print_amount_title:}
+% Emits the \enquote{amount} column title. If all amounts are equal to 1, we
+% emit nothing.
+%
+%    \begin{macrocode}
+\cs_new:Nn {\@@_print_amount_title:}{
+    \bool_if:NT \l_@@_amount_nonone_bool {
+        \@@_print_column_title:n {\GetTranslation{invoice2-amount}} &
+    }
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\@@_print_item_title:}
+% Emits the \enquote{item} column title.
+%
+%    \begin{macrocode}
+\cs_new:Nn {\@@_print_item_title:}{
+    \@@_print_column_title:n {\GetTranslation{invoice2-item}} &
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\@@_print_vat_title:}
+% Emits the \enquote{VAT} column title. If all VATs are zero, we emit nothing.
+%
+%    \begin{macrocode}
+\cs_new:Nn {\@@_print_vat_title:}{
+    \bool_if:NT \l_@@_vat_nonzero_bool {
+        \@@_print_column_title:n {\GetTranslation{invoice2-vat}} &
+    }
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\@@_print_unit_price_title:}
+% Emits the \enquote{unit price} column title. If all amounts are equal to 1,
+% we emit nothing.
+%
+%    \begin{macrocode}
+\cs_new:Nn {\@@_print_unit_price_title:}{
+    \bool_if:NT \l_@@_amount_nonone_bool {
+        \@@_print_column_title:n {\GetTranslation{invoice2-unit-price}} &
+    }
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\@@_print_price_title:}
+% Emits the \enquote{price} column title.
+%
+%    \begin{macrocode}
+\cs_new:Nn {\@@_print_price_title:}{
+    \@@_print_column_title:n {\GetTranslation{invoice2-price}}
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\@@_print_header:}
+% Emits the invoice header. If all amounts are equal to 1, we skip the amount
+% column and the unit price column. If all VATs are 0, we skip the VAT column.
+% 
+%    \begin{macrocode}
+\cs_new:Nn {\@@_print_header:}{
+    \@@_print_begin_table:
+    \toprule
+    \@@_print_amount_title:
+    \@@_print_item_title:
+    \@@_print_vat_title:
+    \@@_print_unit_price_title:
+    \@@_print_price_title:
+    \\
+    \midrule
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \subsection{Content Rendering}
+%
+% \begin{macro}{\@@_print_currency_value:n, \@@_print_currency_value:N}
+% Emits a currency value, formatted with the current settings. The value must
+% be a floating point number or variable.
+% 
+%    \begin{macrocode}
+\cs_new:Nn {\@@_print_currency_value:n}{
+    \num[round-precision={\int_use:N \l_@@_currency_fraction_digits_int},
+    round-mode=places,
+    round-integer-to-decimal,
+    group-minimum-digits=4,
+    group-separator={\GetTranslation{invoice2-thousands-sep}},
+    output-decimal-marker={\GetTranslation{invoice2-decimal-point}}]{
+        #1
+    }
+    \, \tl_use:N \l_@@_currency_symbol_tl
+}
+\cs_new:Nn {\@@_print_currency_value:N}{
+    \@@_print_currency_value:n {\fp_use:N #1}
+}
+%    \end{macrocode}
+% \end{macro}
+%
+%\begin{macro}{\@@_print_percentage:n}
+% Emits a percentage, formatted with the current settings. The value must be a
+% floating point number.
+% 
+%    \begin{macrocode}
+\cs_new:Nn {\@@_print_percentage:n}{
+    \num[round-integer-to-decimal,,
+    group-minimum-digits=4,
+    group-separator={\GetTranslation{invoice2-thousands-sep}},
+    output-decimal-marker={\GetTranslation{invoice2-decimal-point}}]{
+        \fp_eval:n {#1 * 100}
+    }
+    \, \%
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\@@_update_trackers:nn}
+% Update the VAT-not-zero and amount-not-zero trackers for the given VAT and
+% amount values.
+% 
+%    \begin{macrocode}
+\cs_new:Nn {\@@_update_trackers:nn}{
+    \int_compare:nT {#1 != 1}{
+        \bool_set_true:N \l_@@_amount_nonone_bool
+    }
+    \fp_compare:nT {#2 != 0}{
+        \bool_set_true:N \l_@@_vat_nonzero_bool
+    }
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\@@_update_totals:nnn}
+% Update the totals for the given amount, VAT and price per unit values. We 
+% increase the net total by $\tilde{n}$, the VAT total by $\tilde{v}$ and the
+% gross total by $\tilde{g}$. For unit price $p$, amount $a$, VAT $v$ and
+% non-included VATs, this is computed as
+% \begin{align*}
+%    \tilde{n} &= a \cdot p \\
+%    \tilde{v} &= v \cdot \tilde{n} = a \cdot v \cdot p \\
+%    \tilde{g} &= \tilde{n} + \tilde{v} = a \cdot (1 + v) \cdot p, \\
+% \end{align*}
+% for included VATs, as
+% \begin{align*}
+%    \tilde{g} &= a \cdot p \\
+%    \tilde{n} &= \frac{\tilde{g}}{1 + v} = \frac{a \cdot p}{1 + v} \\
+%    \tilde{v} &= \tilde{g} - \tilde{n} = \frac{a \cdot v \cdot p}{1 + v} \\
+% \end{align*}
+% 
+%    \begin{macrocode}
+\cs_new:Nn {\@@_update_totals:nnn}{
+    \fp_add:Nn \l_@@_gross_total_fp {
+        #1 * #3 \bool_if:NF \l_@@_included_vat_bool { * (1 + #2) }
+    }
+    \fp_add:Nn \l_@@_vat_total_fp {
+        #1 * #2 * #3 \bool_if:NT \l_@@_included_vat_bool { / (1 + #2) }
+    }
+    \fp_add:Nn \l_@@_net_total_fp {
+        #1 * #3 \bool_if:NT \l_@@_included_vat_bool { / (1 + #2) }
+    }
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\@@_print_amount:n}
+% Print the given amount value or nothing, if all amounts are one.
+% 
+%    \begin{macrocode}
+\cs_new:Nn {\@@_print_amount:n}{
+    \bool_if:NT \l_@@_amount_nonone_bool {
+        #1 &
+    }
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\@@_print_item:n}
+% Print the given item name.
+% 
+%    \begin{macrocode}
+\cs_new:Nn {\@@_print_item:n}{
+    #1 &
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\@@_print_vat:n}
+% Print the given VAT or nothing, if all VATs are zero.
+% 
+%    \begin{macrocode}
+\cs_new:Nn {\@@_print_vat:n}{
+    \bool_if:NT \l_@@_vat_nonzero_bool {
+        \@@_print_percentage:n {#1} &
+    }
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\@@_print_unit_price:n}
+% Print the given unit price or nothing, if all amounts are one.
+% 
+%    \begin{macrocode}
+\cs_new:Nn {\@@_print_unit_price:n}{
+    \bool_if:NT \l_@@_amount_nonone_bool {
+        \@@_print_currency_value:n {#1} &
+    }
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\@@_print_price:nnn}
+% Print the price $\tilde{p}$ for the current item. Parameters are amount, VAT
+% and price per unit. For unit price $p$, amount $a$, VAT $v$ and non-included
+% VATs, this is computed as
+% \[\tilde{p} = a \cdot (1 + v) \cdot p,\]
+% for included VATs, as
+% \[\tilde{p} = a \cdot p.\]
+% 
+%    \begin{macrocode}
+\cs_new:Nn {\@@_print_price:nnn}{
+    \@@_print_currency_value:n {
+        \fp_eval:n {
+            #1 \bool_if:NF \l_@@_included_vat_bool { * (1 + #2) } * #3
+        }
+    }
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\@@_colorize_row:nnn}
+% Colorize the current row according to even/odd colorization, if color was
+% requested in the configuration.
+% 
+%    \begin{macrocode}
+\cs_new:Nn {\@@_colorize_row:}{
+    \bool_if:NT \l_@@_colorize_bool {
+        \int_if_odd:nTF \g_@@_row_number_int {
+            \rowcolor{ \l_@@_odd_color_tl }
+        }
+        {
+            \rowcolor{ \l_@@_even_color_tl }
+        }
+    }
+    \int_gincr:N \g_@@_row_number_int
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\@@_add_row:nnnn}
+% Add a new entry with non-default VAT to the invoice. This will update the
+% VAT-not-zero and amount-not-zero trackers. Arguments are expected to be (in
+% this order): amount, item name, VAT, unit price.
+% 
+%    \begin{macrocode}
+\cs_new:Nn {\@@_add_row:nnnn}{
+    \@@_update_trackers:nn {#1} {#3}
+    \@@_update_totals:nnn {#1} {#3} {#4}
+    \tl_put_right:Nn \l_@@_tabular_tl {
+        \@@_colorize_row:
+        \@@_print_amount:n {#1}
+        \@@_print_item:n {#2}
+        \@@_print_vat:n {#3}
+        \@@_print_unit_price:n {#4}
+        \@@_print_price:nnn {#1} {#3} {#4} \\
+    }
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\invoiceitem, \invoicesingleitem}
+% This is the user interface to adding items. We read the VAT from the optional
+% argument or the configuration, add an amount of one for single items and
+% delegate to our implementation.
+% 
+%    \begin{macrocode}
+\NewDocumentCommand{\invoiceitem}{ommm}{
+    \@@_add_row:nnnn {#2} {#3}
+    	{\IfValueTF{#1}{#1}{\fp_use:N \l_@@_vat_fp}}
+    	{#4}
+}
+\NewDocumentCommand{\invoicesingleitem}{omm}{
+    \@@_add_row:nnnn {1} {#2}
+        {\IfValueTF{#1}{#1}{\fp_use:N \l_@@_vat_fp}}
+        {#3}
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \subsection{Footer Rendering}
+%
+% \begin{macro}{\@@_print_multicolumn_count:}
+% Emits the column count to group in the final lines. This is the amount of
+% columns minus one.
+% 
+%    \begin{macrocode}
+\cs_new:Nn {\@@_print_multicolumn_count:}{
+    \int_eval:n {
+        1
+        \bool_if:NT \l_@@_vat_nonzero_bool {+1}
+        \bool_if:NT \l_@@_amount_nonone_bool {+2}
+    }
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\@@_print_footer_item:n}
+% Emits a formatted footer item. We also handle colorization of the next cell
+% here.
+% 
+%    \begin{macrocode}
+\cs_new:Nn {\@@_print_footer_item:n}{
+    \multicolumn{\@@_print_multicolumn_count:}{r}{
+        \bool_if:NT \l_@@_colorize_bool {
+            \cellcolor{ \l_@@_total_color_tl }
+        }
+        \textbf{#1}
+    } & \bool_if:NT \l_@@_colorize_bool {
+        \cellcolor{ \l_@@_total_color_tl }
+    }
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\@@_print_net_item:}
+% Emits the \enquote{net total} item.
+% 
+%    \begin{macrocode}
+\cs_new:Nn {\@@_print_net_item:}{
+    \bool_if:NT \l_@@_vat_nonzero_bool {
+        \@@_print_footer_item:n {\GetTranslation{invoice2-net-total}}
+        \@@_print_currency_value:N \l_@@_net_total_fp \\
+    }
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\@@_print_vat_item:}
+% Emits the \enquote{VAT total} item.
+% 
+%    \begin{macrocode}
+\cs_new:Nn {\@@_print_vat_item:}{
+    \bool_if:NT \l_@@_vat_nonzero_bool {
+        \@@_print_footer_item:n {\GetTranslation{invoice2-vat-total}}
+        \@@_print_currency_value:N \l_@@_vat_total_fp \\
+    }
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\@@_print_gross_item:}
+% Emits the \enquote{gross total} item.
+% 
+%    \begin{macrocode}
+\cs_new:Nn {\@@_print_gross_item:}{
+    \@@_print_footer_item:n {\GetTranslation{invoice2-gross-total}}
+    \@@_print_currency_value:N \l_@@_gross_total_fp \\
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\@@_print_footer:}
+% Emits the invoice footer. If all VATs are 0, we skip the net and VAT rows.
+% 
+%    \begin{macrocode}
+\cs_new:Nn {\@@_print_footer:}{
+    \midrule
+    \@@_print_net_item:
+    \@@_print_vat_item:
+    \@@_print_gross_item:
+    \bottomrule
+    \endlongtable
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \subsection{The Environment itself}
+%
+% \begin{macro}{\@@_begin_invoice:n}
+% Begins a new invoice environment. We check for nested environments and set up
+% configuration overrides.
+% 
+%    \begin{macrocode}
+\cs_new:Nn {\@@_begin_invoice:n}{
+    \bool_if:NT \l_@@_in_invoice_bool {
+        \msg_error:nn {invoice2} {nested-invoice}
+    }
+    \bool_set_true:N \l_@@_in_invoice_bool
+    \int_gset:Nn \g_@@_row_number_int {1}
+    \keys_set:nn {invoice2} {#1}
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\@@_end_invoice:}
+% End an invoice enviroenment. Here, we can emit the \cmd{longtable} environment
+% since we possess all required information.
+% 
+%    \begin{macrocode}
+\cs_new:Nn {\@@_end_invoice:}{
+    \@@_print_header:
+    \tl_use:N \l_@@_tabular_tl
+    \@@_print_footer:
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \begin{macro}{\begin{invoice}, \end{invoice}}
+% The user interface is the \cmd{invoice} environment.
+%
+%    \begin{macrocode}
+\NewDocumentEnvironment{invoice}{o}{
+    \IfValueTF{#1}{\@@_begin_invoice:n {#1}}{\@@_begin_invoice:n {}}
+}
+{
+    \@@_end_invoice:
+}
+%    \end{macrocode}
+% \end{macro}
+%
+% \section{Messages and Errors}
+% 
+%    \begin{macrocode}
+\msg_new:nnnn {invoice2} {nested-invoice}
+    {\msg_error_text:n {invoice2}:~%
+    Nested~invoice~environments~are~not~supported.}
+    {Invoices~can~not~contain~invoices.\\%
+    Please~check~your~environment~delimiters.}
+%</package>
+%    \end{macrocode}
+%
+% \section{Dictionary Files}
+% \label{sec:dictionaries}
+%
+% \subsection{English Dictionary}
+%
+%    \begin{macrocode}
+%<*dictEnglish>
+\ProvideDictionaryFor{English}{invoice2}
+\ProvideDictTranslation{invoice2-thousands-sep}{\,}
+\ProvideDictTranslation{invoice2-decimal-point}{.}
+\ProvideDictTranslation{invoice2-amount}{Amount}
+\ProvideDictTranslation{invoice2-item}{Item}
+\ProvideDictTranslation{invoice2-vat}{VAT}
+\ProvideDictTranslation{invoice2-unit-price}{Unit~Price}
+\ProvideDictTranslation{invoice2-price}{Price}
+\ProvideDictTranslation{invoice2-net-total}{Net~Total}
+\ProvideDictTranslation{invoice2-vat-total}{VAT}
+\ProvideDictTranslation{invoice2-gross-total}{Gross~Total}
+%</dictEnglish>
+%    \end{macrocode}
+%
+% \subsection{German Dictionary}
+%
+%    \begin{macrocode}
+%<*dictGerman>
+\ProvideDictionaryFor{German}{invoice2}
+\ProvideDictTranslation{invoice2-thousands-sep}{\,}
+\ProvideDictTranslation{invoice2-decimal-point}{,}
+\ProvideDictTranslation{invoice2-amount}{Anzahl}
+\ProvideDictTranslation{invoice2-item}{Posten}
+\ProvideDictTranslation{invoice2-vat}{MwSt.}
+\ProvideDictTranslation{invoice2-unit-price}{St\"uckpreis}
+\ProvideDictTranslation{invoice2-price}{Preis}
+\ProvideDictTranslation{invoice2-net-total}{Nettobetrag}
+\ProvideDictTranslation{invoice2-vat-total}{MwSt.}
+\ProvideDictTranslation{invoice2-gross-total}{Gesamtbetrag}
+%</dictGerman>
+%    \end{macrocode}
+% \end{implementation}
+%
+% \PrintChanges
+% \PrintIndex
+%
\ No newline at end of file
diff --git a/Master/texmf-dist/source/latex/invoice2/invoice2.ins b/Master/texmf-dist/source/latex/invoice2/invoice2.ins
new file mode 100644
index 00000000000..439925a60e2
--- /dev/null
+++ b/Master/texmf-dist/source/latex/invoice2/invoice2.ins
@@ -0,0 +1,54 @@
+\iffalse meta-comment
+
+File invoice2.ins Copyright (C) 2017 Simon Dierl
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+ 
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+\fi
+
+\input l3docstrip.tex
+\askforoverwritefalse
+
+\preamble
+
+Copyright (C) 2017 Simon Dierl
+
+This program is free software: you can redistribute it and/or modify
+it under the terms of the GNU General Public License as published by
+the Free Software Foundation, either version 3 of the License, or
+(at your option) any later version.
+
+This program is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+GNU General Public License for more details.
+
+You should have received a copy of the GNU General Public License
+along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+\endpreamble
+% stop docstrip adding \endinput
+\postamble
+\endpostamble
+
+\keepsilent
+
+\generate{\file{invoice2.sty} {\from{invoice2.dtx} {package}}}
+\generate{\file{invoice2-english.trsl} {\from{invoice2.dtx} {dictEnglish}}}
+\generate{\file{invoice2-german.trsl} {\from{invoice2.dtx} {dictGerman}}}
+
+\nopreamble\nopostamble
+\generate{\file{README.txt} {\from{invoice2.dtx} {readme}}}
+
+\endbatchfile
diff --git a/Master/texmf-dist/tex/latex/invoice2/invoice2.sty b/Master/texmf-dist/tex/latex/invoice2/invoice2.sty
new file mode 100644
index 00000000000..91b4f5713e5
--- /dev/null
+++ b/Master/texmf-dist/tex/latex/invoice2/invoice2.sty
@@ -0,0 +1,315 @@
+%%
+%% This is file `invoice2.sty',
+%% generated with the docstrip utility.
+%%
+%% The original source files were:
+%%
+%% invoice2.dtx  (with options: `package')
+%% 
+%% Copyright (C) 2017 Simon Dierl
+%% 
+%% This program is free software: you can redistribute it and/or modify
+%% it under the terms of the GNU General Public License as published by
+%% the Free Software Foundation, either version 3 of the License, or
+%% (at your option) any later version.
+%% 
+%% This program is distributed in the hope that it will be useful,
+%% but WITHOUT ANY WARRANTY; without even the implied warranty of
+%% MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+%% GNU General Public License for more details.
+%% 
+%% You should have received a copy of the GNU General Public License
+%% along with this program.  If not, see <http://www.gnu.org/licenses/>.
+%% 
+\RequirePackage{booktabs}
+\RequirePackage{expl3}
+\RequirePackage{l3keys2e}
+\RequirePackage{longtable}
+\RequirePackage{siunitx}
+\RequirePackage{translations}
+\RequirePackage[table]{xcolor}
+\RequirePackage{xparse}
+\ProvidesExplPackage{invoice2}{2017/07/15}{1.0}
+    {Next-generation invoice typesetting with booktabs}
+\LoadDictionaryFor{english}{invoice2}
+\LoadDictionaryFor{german}{invoice2}
+\DeclareTranslationFallback{invoice2-thousands-sep}{\,}
+\DeclareTranslationFallback{invoice2-decimal-point}{.}
+\DeclareTranslationFallback{invoice2-amount}{Amount}
+\DeclareTranslationFallback{invoice2-item}{Item}
+\DeclareTranslationFallback{invoice2-vat}{VAT}
+\DeclareTranslationFallback{invoice2-unit-price}{Unit~Price}
+\DeclareTranslationFallback{invoice2-price}{Price}
+\DeclareTranslationFallback{invoice2-net-total}{Net~Total}
+\DeclareTranslationFallback{invoice2-vat-total}{VAT}
+\DeclareTranslationFallback{invoice2-gross-total}{Gross~Total}
+\fp_new:N \l__invoicetwo_vat_fp
+\bool_new:N \l__invoicetwo_included_vat_bool
+\tl_new:N \l__invoicetwo_currency_symbol_tl
+\int_new:N \l__invoicetwo_currency_fraction_digits_int
+\bool_new:N \l__invoicetwo_colorize_bool
+\tl_new:N \l__invoicetwo_odd_color_tl
+\tl_set:Nn \l__invoicetwo_odd_color_tl {white}
+\tl_new:N \l__invoicetwo_even_color_tl
+\tl_set:Nn \l__invoicetwo_even_color_tl {lightgray}
+\tl_new:N \l__invoicetwo_title_color_tl
+\tl_set:Nn \l__invoicetwo_title_color_tl {white}
+\tl_new:N \l__invoicetwo_total_color_tl
+\tl_set:Nn \l__invoicetwo_total_color_tl {white}
+\bool_new:N \l__invoicetwo_in_invoice_bool
+\int_new:N \g__invoicetwo_row_number_int
+\bool_new:N \l__invoicetwo_vat_nonzero_bool
+\bool_new:N \l__invoicetwo_amount_nonone_bool
+\fp_new:N \l__invoicetwo_net_total_fp
+\fp_new:N \l__invoicetwo_vat_total_fp
+\fp_new:N \l__invoicetwo_gross_total_fp
+\tl_new:N \l__invoicetwo_tabular_tl
+\keys_define:nn {invoice2} {
+    vat .fp_set:N = \l__invoicetwo_vat_fp,
+    vat .value_required:n = true,
+    vat .initial:n = 0,
+    included-vat .bool_set:N = \l__invoicetwo_included_vat_bool,
+    included-vat .initial:n = false,
+    currency-symbol .tl_set:N = \l__invoicetwo_currency_symbol_tl,
+    currency-symbol .value_required:n = true,
+    currency-symbol .initial:n = {\$},
+    currency-fraction-digits .int_set:N = \l__invoicetwo_currency_fraction_digits_int,
+    currency-fraction-digits .value_required:n = true,
+    currency-fraction-digits .initial:n = 2,
+    colorize .bool_set:N = \l__invoicetwo_colorize_bool,
+    colorize .initial:n = false,
+    odd-color .initial:n = white,
+    odd-color .value_required:n = true,
+    odd-color .tl_set:N = \l__invoicetwo_odd_color_tl,
+    even-color .initial:n = lightgray,
+    even-color .value_required:n = true,
+    even-color .tl_set:N = \l__invoicetwo_even_color_tl,
+    title-color .initial:n = white,
+    title-color .value_required:n = true,
+    title-color .tl_set:N = \l__invoicetwo_title_color_tl,
+    total-color .initial:n = white,
+    total-color .value_required:n = true,
+    total-color .tl_set:N = \l__invoicetwo_total_color_tl
+}
+\ProcessKeysOptions{invoice2}
+\NewDocumentCommand{\invoiceoptions}{m}{
+    \keys_set:nn {invoice2} {#1}
+}
+\cs_new:Nn {\__invoicetwo_print_begin_table:}{
+\exp_args:Nx \longtable {
+\bool_if:NT \l__invoicetwo_amount_nonone_bool { c }
+l
+\bool_if:NT \l__invoicetwo_vat_nonzero_bool { c }
+r
+\bool_if:NT \l__invoicetwo_amount_nonone_bool { r }
+}
+}
+\cs_new:Nn {\__invoicetwo_print_column_title:n}{
+    \multicolumn{1}{c}{
+        \bool_if:NT \l__invoicetwo_colorize_bool {
+            \cellcolor{ \l__invoicetwo_title_color_tl }
+        }
+        \begin{scriptsize}
+            \textbf{#1}
+        \end{scriptsize}}
+}
+\cs_new:Nn {\__invoicetwo_print_amount_title:}{
+    \bool_if:NT \l__invoicetwo_amount_nonone_bool {
+        \__invoicetwo_print_column_title:n {\GetTranslation{invoice2-amount}} &
+    }
+}
+\cs_new:Nn {\__invoicetwo_print_item_title:}{
+    \__invoicetwo_print_column_title:n {\GetTranslation{invoice2-item}} &
+}
+\cs_new:Nn {\__invoicetwo_print_vat_title:}{
+    \bool_if:NT \l__invoicetwo_vat_nonzero_bool {
+        \__invoicetwo_print_column_title:n {\GetTranslation{invoice2-vat}} &
+    }
+}
+\cs_new:Nn {\__invoicetwo_print_unit_price_title:}{
+    \bool_if:NT \l__invoicetwo_amount_nonone_bool {
+        \__invoicetwo_print_column_title:n {\GetTranslation{invoice2-unit-price}} &
+    }
+}
+\cs_new:Nn {\__invoicetwo_print_price_title:}{
+    \__invoicetwo_print_column_title:n {\GetTranslation{invoice2-price}}
+}
+\cs_new:Nn {\__invoicetwo_print_header:}{
+    \__invoicetwo_print_begin_table:
+    \toprule
+    \__invoicetwo_print_amount_title:
+    \__invoicetwo_print_item_title:
+    \__invoicetwo_print_vat_title:
+    \__invoicetwo_print_unit_price_title:
+    \__invoicetwo_print_price_title:
+    \\
+    \midrule
+}
+\cs_new:Nn {\__invoicetwo_print_currency_value:n}{
+    \num[round-precision={\int_use:N \l__invoicetwo_currency_fraction_digits_int},
+    round-mode=places,
+    round-integer-to-decimal,
+    group-minimum-digits=4,
+    group-separator={\GetTranslation{invoice2-thousands-sep}},
+    output-decimal-marker={\GetTranslation{invoice2-decimal-point}}]{
+        #1
+    }
+    \, \tl_use:N \l__invoicetwo_currency_symbol_tl
+}
+\cs_new:Nn {\__invoicetwo_print_currency_value:N}{
+    \__invoicetwo_print_currency_value:n {\fp_use:N #1}
+}
+\cs_new:Nn {\__invoicetwo_print_percentage:n}{
+    \num[round-integer-to-decimal,,
+    group-minimum-digits=4,
+    group-separator={\GetTranslation{invoice2-thousands-sep}},
+    output-decimal-marker={\GetTranslation{invoice2-decimal-point}}]{
+        \fp_eval:n {#1 * 100}
+    }
+    \, \%
+}
+\cs_new:Nn {\__invoicetwo_update_trackers:nn}{
+    \int_compare:nT {#1 != 1}{
+        \bool_set_true:N \l__invoicetwo_amount_nonone_bool
+    }
+    \fp_compare:nT {#2 != 0}{
+        \bool_set_true:N \l__invoicetwo_vat_nonzero_bool
+    }
+}
+\cs_new:Nn {\__invoicetwo_update_totals:nnn}{
+    \fp_add:Nn \l__invoicetwo_gross_total_fp {
+        #1 * #3 \bool_if:NF \l__invoicetwo_included_vat_bool { * (1 + #2) }
+    }
+    \fp_add:Nn \l__invoicetwo_vat_total_fp {
+        #1 * #2 * #3 \bool_if:NT \l__invoicetwo_included_vat_bool { / (1 + #2) }
+    }
+    \fp_add:Nn \l__invoicetwo_net_total_fp {
+        #1 * #3 \bool_if:NT \l__invoicetwo_included_vat_bool { / (1 + #2) }
+    }
+}
+\cs_new:Nn {\__invoicetwo_print_amount:n}{
+    \bool_if:NT \l__invoicetwo_amount_nonone_bool {
+        #1 &
+    }
+}
+\cs_new:Nn {\__invoicetwo_print_item:n}{
+    #1 &
+}
+\cs_new:Nn {\__invoicetwo_print_vat:n}{
+    \bool_if:NT \l__invoicetwo_vat_nonzero_bool {
+        \__invoicetwo_print_percentage:n {#1} &
+    }
+}
+\cs_new:Nn {\__invoicetwo_print_unit_price:n}{
+    \bool_if:NT \l__invoicetwo_amount_nonone_bool {
+        \__invoicetwo_print_currency_value:n {#1} &
+    }
+}
+\cs_new:Nn {\__invoicetwo_print_price:nnn}{
+    \__invoicetwo_print_currency_value:n {
+        \fp_eval:n {
+            #1 \bool_if:NF \l__invoicetwo_included_vat_bool { * (1 + #2) } * #3
+        }
+    }
+}
+\cs_new:Nn {\__invoicetwo_colorize_row:}{
+    \bool_if:NT \l__invoicetwo_colorize_bool {
+        \int_if_odd:nTF \g__invoicetwo_row_number_int {
+            \rowcolor{ \l__invoicetwo_odd_color_tl }
+        }
+        {
+            \rowcolor{ \l__invoicetwo_even_color_tl }
+        }
+    }
+    \int_gincr:N \g__invoicetwo_row_number_int
+}
+\cs_new:Nn {\__invoicetwo_add_row:nnnn}{
+    \__invoicetwo_update_trackers:nn {#1} {#3}
+    \__invoicetwo_update_totals:nnn {#1} {#3} {#4}
+    \tl_put_right:Nn \l__invoicetwo_tabular_tl {
+        \__invoicetwo_colorize_row:
+        \__invoicetwo_print_amount:n {#1}
+        \__invoicetwo_print_item:n {#2}
+        \__invoicetwo_print_vat:n {#3}
+        \__invoicetwo_print_unit_price:n {#4}
+        \__invoicetwo_print_price:nnn {#1} {#3} {#4} \\
+    }
+}
+\NewDocumentCommand{\invoiceitem}{ommm}{
+    \__invoicetwo_add_row:nnnn {#2} {#3}
+     {\IfValueTF{#1}{#1}{\fp_use:N \l__invoicetwo_vat_fp}}
+     {#4}
+}
+\NewDocumentCommand{\invoicesingleitem}{omm}{
+    \__invoicetwo_add_row:nnnn {1} {#2}
+        {\IfValueTF{#1}{#1}{\fp_use:N \l__invoicetwo_vat_fp}}
+        {#3}
+}
+\cs_new:Nn {\__invoicetwo_print_multicolumn_count:}{
+    \int_eval:n {
+        1
+        \bool_if:NT \l__invoicetwo_vat_nonzero_bool {+1}
+        \bool_if:NT \l__invoicetwo_amount_nonone_bool {+2}
+    }
+}
+\cs_new:Nn {\__invoicetwo_print_footer_item:n}{
+    \multicolumn{\__invoicetwo_print_multicolumn_count:}{r}{
+        \bool_if:NT \l__invoicetwo_colorize_bool {
+            \cellcolor{ \l__invoicetwo_total_color_tl }
+        }
+        \textbf{#1}
+    } & \bool_if:NT \l__invoicetwo_colorize_bool {
+        \cellcolor{ \l__invoicetwo_total_color_tl }
+    }
+}
+\cs_new:Nn {\__invoicetwo_print_net_item:}{
+    \bool_if:NT \l__invoicetwo_vat_nonzero_bool {
+        \__invoicetwo_print_footer_item:n {\GetTranslation{invoice2-net-total}}
+        \__invoicetwo_print_currency_value:N \l__invoicetwo_net_total_fp \\
+    }
+}
+\cs_new:Nn {\__invoicetwo_print_vat_item:}{
+    \bool_if:NT \l__invoicetwo_vat_nonzero_bool {
+        \__invoicetwo_print_footer_item:n {\GetTranslation{invoice2-vat-total}}
+        \__invoicetwo_print_currency_value:N \l__invoicetwo_vat_total_fp \\
+    }
+}
+\cs_new:Nn {\__invoicetwo_print_gross_item:}{
+    \__invoicetwo_print_footer_item:n {\GetTranslation{invoice2-gross-total}}
+    \__invoicetwo_print_currency_value:N \l__invoicetwo_gross_total_fp \\
+}
+\cs_new:Nn {\__invoicetwo_print_footer:}{
+    \midrule
+    \__invoicetwo_print_net_item:
+    \__invoicetwo_print_vat_item:
+    \__invoicetwo_print_gross_item:
+    \bottomrule
+    \endlongtable
+}
+\cs_new:Nn {\__invoicetwo_begin_invoice:n}{
+    \bool_if:NT \l__invoicetwo_in_invoice_bool {
+        \msg_error:nn {invoice2} {nested-invoice}
+    }
+    \bool_set_true:N \l__invoicetwo_in_invoice_bool
+    \int_gset:Nn \g__invoicetwo_row_number_int {1}
+    \keys_set:nn {invoice2} {#1}
+}
+\cs_new:Nn {\__invoicetwo_end_invoice:}{
+    \__invoicetwo_print_header:
+    \tl_use:N \l__invoicetwo_tabular_tl
+    \__invoicetwo_print_footer:
+}
+\NewDocumentEnvironment{invoice}{o}{
+    \IfValueTF{#1}{\__invoicetwo_begin_invoice:n {#1}}{\__invoicetwo_begin_invoice:n {}}
+}
+{
+    \__invoicetwo_end_invoice:
+}
+\msg_new:nnnn {invoice2} {nested-invoice}
+    {\msg_error_text:n {invoice2}:~%
+    Nested~invoice~environments~are~not~supported.}
+    {Invoices~can~not~contain~invoices.\\%
+    Please~check~your~environment~delimiters.}
+%% 
+%%
+%% End of file `invoice2.sty'.