relax SVN archive

Created the molecule.create() user function.

The user function and the function generic_fns.molecule.create() have been written. Two unit tests
for the function have been created.

Updated the module names in '__init__.py'.

Replace the contents of 'generic_fns/molecule.py' with those of 'generic_fns/residue.py'.

The file originated from 'generic_fns/residue.py' but was unmodified and out of date.

Added the setUp and tearDown functions for the generic_fns.molecule function unit tests.

Created the module docstring.

Spacing.

Added a module docstring.

Removed some no longer used RelaxError imports.

Removed junk code, left over from the copy from 'generic_fns/sequence.py'.

Modified the data model redesign document to show that the residue user function class is finished.