relax SVN archive

Updated the manual and changed the version number to 1.2.9.

Ported r2783 from the 1.2.9 tag (the CHANGES file details for relax version 1.2.9).

The command used was:
svn merge -r2782:2783 svn+ssh://bugman@.../svn/relax/tags/1.2.9

Ported r2783 from the 1.2.9 tag (the CHANGES file details for relax version 1.2.9).

The command used was:
svn merge -r2782:2783 svn+ssh://bugman@.../svn/relax/tags/1.2.9

Updated the CHANGES file for relax version 1.2.9.

relax version 1.2.9.

This release includes r2742 to r2780 of the 1.2 line. This is a quick bugfix release which fixes
bug #7641 (http://gna.org/bugs/?7641), the infinite chi-squared RelaxError when the chi-squared
value is zero.

Ported r2780 from the 1.2 line.

The command used was:
svn merge -r2779:2780 svn+ssh://bugman@.../svn/relax/1.2

This changes the interpreter from '/usr/bin/python' to '/usr/bin/env python'.

Changed the interpreter from '/usr/bin/python' to '/usr/bin/env python'.

This changes the first line of the 'relax' file. The change was suggested by Douglas Kojetin
(douglas dot kojetin at gmail dot com) in the post located at
https://mail.gna.org/public/relax-devel/2006-11/msg00098.html (Message-id:
<0E180DBB-896A-45F6-B19D-D6A02FD2BA4A@...>).

The change allows relax to run on Mac OS X by just typing 'relax'. This is because the python
binary is located at '/sw/bin/python'.

Ported r2745, r2746, and r2778 from the 1.2 line.

The commands used were:
svn merge -r2744:2746 svn+ssh://bugman@.../svn/relax/1.2
svn merge -r2777:2778 svn+ssh://bugman@.../svn/relax/1.2

This includes editing of the release checklist file, a spell check of the CHANGES file, and the fix
to bug #7677 (https://gna.org/bugs/index.php?7677).

Fix for bug #7677 (https://gna.org/bugs/index.php?7677).

The fix was simply to add the dummy keyword argument "status=0" to the end of the argument list of
the 'print_stats()' statistics sorting and printing function.

Added tests for isZero & isPositive & id based dicts and subset removal