relax SVN archive

Corrected a small typo in the development chapter of the manual.

Created a branch for the implementation of the relaxation dispersion code.

This follows a thread started by Seb at:
https://mail.gna.org/public/relax-devel/2008-12/msg00058.html
(Message-id: <4951148F.9050105@...>)

and continued by Ed at:
https://mail.gna.org/public/relax-devel/2009-01/msg00003.html
(Message-id: <7f080ed10901060854v3e0c1ac6idb8fad319e43c7de@...>)

Many corrections of formatting.

These were found using the relax 'code_validator' script (E. d'Auvergne) and mainly include trailing
whitespaces and missing empty lines before functions.

Add structural object load_pdb() methods now take the read_mol, set_mol_name, read_model, set_model_num args.

Fixes for 3 model-free unit tests using generic_fns.structure.main.read_pdb().

Passed the new args into generic_fns.structure.main.read_pdb().

Redesigned the structure.read_pdb() arguments and docstring.

Fixes for 4 of the structure.read_pdb() user function arg unit tests.

Removed the model arg unit test of structure.read_pdb() and added 4 new tests.

Created the new RelaxNoneStrListStrError error class and fixed the RelaxNoneStrListError print out.