relax SVN archive

Changed the format of the PDB representation of the XH vector distribution.

Each XH pair is being created as a proper vector with two atoms rather than all protons connecting
back to a single centre of mass.

Added the method 'self.create_vector_dist()' to 'generic_fns/structure.py'.

This function currently calculates and adds the centre of mass to the PDB file, adds the XH vectors
as protons to the 'self.atomic_data' data structure, and creates the PDB file. The code is
incomplete as each vector is being set to the true residue name and number and ATM record support
still needs to be added.

Started to created the 'structure.create_vector_dist()' user function.

This function will, when completed, create a PDB representation of the XH bond vectors from the
structure.

Spun out the XH bond vector calculation code into its own function 'self.xh_vector()'.

Renamed all instances of 'create_tensor_pdb' to 'create_diff_tensor_pdb'.

Fixes for the script for creating the PDB representation of the diffusion tensor.

Added a sample script for the creation of the PDB representation of the diffusion tensor.

Ported r2912 from the 1.3 line.

The command used was:
svn merge -r2911:2912 svn+ssh://bugman@.../svn/relax/1.3

These changes are improvements to the model-free optimisation protocol flow diagrams.

Improvements to the model-free optimisation protocol flow diagrams.

Fixed the running of the test suite through the --test-suite command line flag.