relax SVN archive

Changed the default arg values for the openfile GUI element.

Added a package for user function GUI elements.

Created a menu called 'User functions', and added the first entry 'script'.

Renumbered the help menu entries.

The molecule icon is now shown in the tree view.

The molecule icon is now included in the icon paths.

Created an svg icon for the molecule part of the tree view.

The derived 48x48 bitmap is also included.

Bug fix for a number of missing ':' characters, and comment improvements.

Introduction of looping over the relaxation interactions.

This is the application of patch00004 by Pavel Kaderavek <pavel dot kaderavek att gmail dot com>.
The patch is attached to task #6397 (https://gna.org/task/?6397).

This patch introduces the looping over all relaxation interactions within the model-free target
functions.

Built a tree view GUI element for the molecule, residue, and spin data.

This is a very basic element currently shown in a window. The 'View->Show tree view' menu entry is
currently commented out. This will be used as a basis for future expansion of the GUI.