GNOME UI planned deprecation

[bostrt]

According to http://library.gnome.org/devel/references GNOME UI is heading towards planned deprecation. The link also states that many of the widgets from libgnomeui have been ported to GTK+. We need to convert all widgets over to GTK+ and remove libgnomeui as a dependency.

[bostrt]

Started new branch

[dwest]

We should probably work on this next time we have a hackfest because I need to work the gconf callbacks into all of the widgets anyway. If we switch everything over to GTK+ at the same time we could kill two birds with one stone.