relax SVN archive

Rewrote the docstring of the 'self.write_pdb_file()' function to include PDB record descriptions.

Desriptions of the PDB records HET, HETNAM, FORMUL, HETATM, TER, CONECT, MASTER, and END including
tables of columns, data type, field, and definition have been added. This info comes from the
"Protein Data Bank Contents Guide: Atomic Coordinate Entry Format Description" version 2.1 (draft),
October 25, 1996.

Fixed the spelling of 'infinite' in the 1.2.8 release details.

A few small edits of the release checklist and fixed the scons target 'user_manual_html'.

Updated the manual and changed the version number to 1.2.8.

Ported r2741 from the 1.2.8 tag (the CHANGES file details for 1.2.8).

The command used was:
svn merge -r2740:2741 svn+ssh://bugman@.../svn/relax/tags/1.2.8

Ported r2741 from the 1.2.8 tag (the CHANGES file details for 1.2.8).

The command used was:
svn merge -r2740:2741 svn+ssh://bugman@.../svn/relax/tags/1.2.8

Updated the CHANGES file for relax version 1.2.8.

relax version 1.2.8.

This is a major bug fix release. All users who encounter problems are recommended to upgrade to
this version. Optimisation tests have also been added to the test suite.

Ported r2738 from the 1.2 line.

The command used was:
svn merge -r2737:2738 svn+ssh://bugman@.../svn/relax/1.2

This fixes the massively important bug #7616 (https://gna.org/bugs/index.php?7616) which is the
failure of the model selection between the global diffusion models when the local tm models are
included.

Fix for bug #7616 (https://gna.org/bugs/index.php?7616).

This fixes the failure of the model selection between the global diffusion models when the local tm
models are included. This is a very important bug fix.

The 'model_statistics()' function in the model-free and hybrid files have been modified. The
'min_instances' argument to the function was not being utilised at all since r2516
(https://mail.gna.org/public/relax-commits/2006-07/msg00010.html) which introduced this bug. The
argument has been renamed to 'global_stats'. This 'global_stats' argument is feed in solely by the
model selection code. That code decides if global statistics (which are summed for the local tm
models) should be utilised using the test:

if self.num_instances[j] > self.min_instances or self.num_instances[j] == 1:

The model selection function, if the global stats argument is 1 and 'self.param_set' is equal to
'local_tm', will sum the chi2 values of the individual local tm models and return that value.

To fix an issue with the OpenDX code causing a failure of the test suite, the 'min_instances'
argument in the call to the model statistics function has been dropped.