relax SVN archive

Bug fix for the internal relax PDB data object.

The object structural_data inside the data object was a class variable, and hence each instantiation
of Internal_PDB was not resetting the object. If the object was used twice, then the data from the
first would remain.

Same bug fix as in r5412 but for tensor_pdb().

Same bug fix as in r5411 but for tensor_pdb().

Another bug fix for the cone_pdb() function.

The pymol 'load' command requires the full PDB file name.

Bug fix for the cone_pdb() function.

'pdb_file' does not exist.

Created the cone_pdb() function for displaying the N-state model cone object in PyMOL.

Added the return details to the create_macro() docstring.

Arg to keyword epydoc fix.

Updated the write() function to the new relax design.

Updated the vector_dist() function to the new relax design.