relax SVN archive

Fixed a typo in the docstrings of the unit tests for the generic_fns.residue functions.

Created the residue.display() user function.

This has been added to the data model redesign document. Two unit tests have also been created for
the function.

Created the residue.renumber() user function.

Added the residue.rename() user function.

Updated the docstring modifications of the 'residue' user function class.

Removed dud user functions from 'residue' which remained from the copy of 'sequence'.

Replaced all mention of 'run' from the RelaxError system and replaced it with 'pipe'.

Renamed all instances of RelaxRunError with RelaxPipeError, and modified the error message.

Renamed all instances of RelaxNoRunError to RelaxNoPipeError, and updated the error message.

Added two unit tests for the generic_fns.selection.return_single_residue_info() function.