Copyright (c) 2013 Dmitry Galinsky

The GNU General Public License, Version 2, June 1991 (GPLv2)
============================================================

> Copyright (C) 1989, 1991 Free Software Foundation, Inc.
> 59 Temple Place, Suite 330
> Boston, MA  02111-1307 USA

Everyone is permitted to copy and distribute verbatim copies of this license
document, but changing it is not allowed.


Preamble
--------

The licenses for most software are designed to take away your freedom to share
and change it. By contrast, the GNU General Public License is intended to
guarantee your freedom to share and change free software--to make sure the
software is free for all its users. This General Public License applies to most
of the Free Software Foundation's software and to any other program whose
authors commit to using it. (Some other Free Software Foundation software is
covered by the GNU Library General Public License instead.) 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 this service 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 make restrictions that forbid anyone to deny
you these rights or to ask you to surrender the rights. These restrictions
translate to certain responsibilities for you if you distribute copies of the
software, or if you modify it.

For example, if you distribute copies of such a program, whether gratis or for a
fee, you must give the recipients all the rights that you have. 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.

We protect your rights with two steps: (1) copyright the software, and (2) offer
you this license which gives you legal permission to copy, distribute and/or
modify the software.

Also, for each author's protection and ours, we want to make certain that
everyone understands that there is no warranty for this free software. If the
software is modified by someone else and passed on, we want its recipients to
know that what they have is not the original, so that any problems introduced by
others will not reflect on the original authors' reputations.

Finally, any free program is threatened constantly by software patents. We wish
to avoid the danger that redistributors of a free program will individually
obtain patent licenses, in effect making the program proprietary. To prevent
this, we have made it clear that any patent must be licensed for everyone's free
use or not licensed at all.

The precise terms and conditions for copying, distribution and modification
follow.


Terms And Conditions For Copying, Distribution And Modification
---------------------------------------------------------------
0.  This License applies to any program or other work which contains a notice
    placed by the copyright holder saying it may be distributed under the terms
    of this General Public License. The "Program", below, refers to any such
    program or work, and a "work based on the Program" means either the Program
    or any derivative work under copyright law: that is to say, a work
    containing the Program or a portion of it, either verbatim or with
    modifications and/or translated into another language. (Hereinafter,
    translation is included without limitation in the term "modification".)
    Each licensee is addressed as "you".

    Activities other than copying, distribution and modification are not
    covered by this License; they are outside its scope. The act of running the
    Program is not restricted, and the output from the Program is covered only
    if its contents constitute a work based on the Program (independent of
    having been made by running the Program). Whether that is true depends on
    what the Program does.

1.  You may copy and distribute 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 and
    disclaimer of warranty; keep intact all the notices that refer to this
    License and to the absence of any warranty; and give any other recipients
    of the Program a copy of this License along with the Program.

    You may charge a fee for the physical act of transferring a copy, and you
    may at your option offer warranty protection in exchange for a fee.

2.  You may modify your copy or copies of the Program or any portion of it,
    thus forming a work based on the Program, and copy and distribute such
    modifications or work under the terms of Section 1 above, provided that you
    also meet all of these conditions:

    a)  You must cause the modified files to carry prominent notices stating
        that you changed the files and the date of any change.

    b)  You must cause any work that you distribute or publish, that in whole
        or in part contains or is derived from the Program or any part thereof,
        to be licensed as a whole at no charge to all third parties under the
        terms of this License.

    c)  If the modified program normally reads commands interactively when run,
        you must cause it, when started running for such interactive use in the
        most ordinary way, to print or display an announcement including an
        appropriate copyright notice and a notice that there is no warranty (or
        else, saying that you provide a warranty) and that users may
        redistribute the program under these conditions, and telling the user
        how to view a copy of this License. (Exception: if the Program itself
        is interactive but does not normally print such an announcement, your
        work based on the Program is not required to print an announcement.)

    These requirements apply to the modified work as a whole. If identifiable
    sections of that work are not derived from the Program, and can be
    reasonably considered independent and separate works in themselves, then
    this License, and its terms, do not apply to those sections when you
    distribute them as separate works. But when you distribute the same
    sections as part of a whole which is a work based on the Program, the
    distribution of the whole must be on the terms of this License, whose
    permissions for other licensees extend to the entire whole, and thus to
    each and every part regardless of who wrote it.

    Thus, it is not the intent of this section to claim rights or contest your
    rights to work written entirely by you; rather, the intent is to exercise
    the right to control the distribution of derivative or collective works
    based on the Program.

    In addition, mere aggregation of another work not based on the Program with
    the Program (or with a work based on the Program) on a volume of a storage
    or distribution medium does not bring the other work under the scope of
    this License.

3.  You may copy and distribute the Program (or a work based on it, under
    Section 2) in object code or executable form under the terms of Sections 1
    and 2 above provided that you also do one of the following:

    a)  Accompany it with the complete corresponding machine-readable source
        code, which must be distributed under the terms of Sections 1 and 2
        above on a medium customarily used for software interchange; or,

    b)  Accompany it with a written offer, valid for at least three years, to
        give any third party, for a charge no more than your cost of physically
        performing source distribution, a complete machine-readable copy of the
        corresponding source code, to be distributed under the terms of
        Sections 1 and 2 above on a medium customarily used for software
        interchange; or,

    c)  Accompany it with the information you received as to the offer to
        distribute corresponding source code. (This alternative is allowed only
        for noncommercial distribution and only if you received the program in
        object code or executable form with such an offer, in accord with
        Subsection b above.)

    The source code for a work means the preferred form of the work for making
    modifications to it. For an executable work, complete source code means all
    the source code for all modules it contains, plus any associated interface
    definition files, plus the scripts used to control compilation and
    installation of the executable. However, as a special exception, the source
    code distributed need not include anything that is normally distributed (in
    either source or binary form) with the major components (compiler, kernel,
    and so on) of the operating system on which the executable runs, unless
    that component itself accompanies the executable.

    If distribution of executable or object code is made by offering access to
    copy from a designated place, then offering equivalent access to copy the
    source code from the same place counts as distribution of the source code,
    even though third parties are not compelled to copy the source along with
    the object code.

4.  You may not copy, modify, sublicense, or distribute the Program except as
    expressly provided under this License. Any attempt otherwise to copy,
    modify, sublicense or distribute the Program is void, and will
    automatically terminate your rights under this License. However, parties
    who have received copies, or rights, from you under this License will not
    have their licenses terminated so long as such parties remain in full
    compliance.

5.  You are not required to accept this License, since you have not signed it.
    However, nothing else grants you permission to modify or distribute the
    Program or its derivative works. These actions are prohibited by law if you
    do not accept this License. Therefore, by modifying or distributing the
    Program (or any work based on the Program), you indicate your acceptance of
    this License to do so, and all its terms and conditions for copying,
    distributing or modifying the Program or works based on it.

6.  Each time you redistribute the Program (or any work based on the Program),
    the recipient automatically receives a license from the original licensor
    to copy, distribute or modify the Program subject to these terms and
    conditions. You may not impose any further restrictions on the recipients'
    exercise of the rights granted herein. You are not responsible for
    enforcing compliance by third parties to this License.

7.  If, as a consequence of a court judgment or allegation of patent
    infringement or for any other reason (not limited to patent issues),
    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 distribute so
    as to satisfy simultaneously your obligations under this License and any
    other pertinent obligations, then as a consequence you may not distribute
    the Program at all. For example, if a patent license would not permit
    royalty-free redistribution of the Program by all those who receive copies
    directly or indirectly through you, then the only way you could satisfy
    both it and this License would be to refrain entirely from distribution of
    the Program.

    If any portion of this section is held invalid or unenforceable under any
    particular circumstance, the balance of the section is intended to apply
    and the section as a whole is intended to apply in other circumstances.

    It is not the purpose of this section to induce you to infringe any patents
    or other property right claims or to contest validity of any such claims;
    this section has the sole purpose of protecting the integrity of the free
    software distribution system, which is implemented by public license
    practices. Many people have made generous contributions to the wide range
    of software distributed through that system in reliance on consistent
    application of that system; it is up to the author/donor to decide if he or
    she is willing to distribute software through any other system and a
    licensee cannot impose that choice.

    This section is intended to make thoroughly clear what is believed to be a
    consequence of the rest of this License.

8.  If the distribution and/or use of the Program is restricted in certain
    countries either by patents or by copyrighted interfaces, the original
    copyright holder who places the Program under this License may add an
    explicit geographical distribution limitation excluding those countries, so
    that distribution is permitted only in or among countries not thus excluded.
    In such case, this License incorporates the limitation as if written in
    the body of this License.

9.  The Free Software Foundation may publish revised and/or new versions of the
    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 a version number of this License which applies to it and "any
    later version", you have the option of following the terms and conditions
    either of that version or of any later version published by the Free
    Software Foundation. If the Program does not specify a version number of
    this License, you may choose any version ever published by the Free
    Software Foundation.

10. If you wish to incorporate parts of the Program into other free programs
    whose distribution conditions are different, write to the author to ask for
    permission. For software which is copyrighted by the Free Software
    Foundation, write to the Free Software Foundation; we sometimes make
    exceptions for this. Our decision will be guided by the two goals of
    preserving the free status of all derivatives of our free software and of
    promoting the sharing and reuse of software generally.


No Warranty
-----------

11. BECAUSE THE PROGRAM IS LICENSED FREE OF CHARGE, 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.

12. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN WRITING WILL
    ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY AND/OR REDISTRIBUTE
    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.