relax SVN archive

The user function GUI menu item is now being auto-generated.

This will require future work to support user functions not within a user function class.

The graphics.fetch_icon() function now returns None if no icon is specified.

Created the graphics.fetch_icon() function for a better API for the icon paths.

This will eventually replace the gui.paths module.

The graphics directory has been converted into a Python package.

This will be used to store special functions related to graphics manipulation, retrieval, etc.

Renamed the gui.user_functions package to gui.uf_pages to avoid import clashes.

This package was clashing with the base user_functions package, breaking imports everywhere.

Started to write the auto-generated user function GUI menu.

Created methods for returning user function and class data objects from the user function data object.

These are called get_class() and get_uf().

Fix for the bmrb.citation user function prompt front end.

The status argument was hiding the relax status singleton object!

Updated the user_function and prompt packages __all__ lists.

The auto-generated prompt user function front end objects are now executable.

The uf.backend variable is now the executable Python object. The pipe user function class has been
updated for the uf.backend change.