relax SVN archive

Shifted the 'user function' sub-menu construction into _user_functions().

Shifted out the GUI main menu bar into its own module.

Improvements to the unfolded molecule icon - there is now residual structure!

The molecule icon changes from folded to unfolded as the tree is opened and closed.

Added the unfolded molecule icon to the paths module.

Added an basic icon for an unfolded molecule.

The 'Spin tree view' menu entry has been renamed to 'Spin view', and the spin icon is now used.

Added the molecule, residue, and spin 16x16 icons to the icon paths.

Rearrangement and ordering of the icon paths into classes for the different sizes.

Each icon size is now placed into its own class.

Created 16x16 pixel versions of the molecule, residue, and spin icons.