Dynamic menus

[Lars Ræder <larsrc gmail com>]

Since the changelog daemon seems to be on strike, here's a little
heads-up on a new feature that got committed yesterday, and that I'd
like feedback on:  Dynamic menus.  For (so far) sheets, arrow heads
(in properties dialogs) and fonts, Dia now uses a short menu with the
standard items and the most recently used items, and a submenu that
contains the full list.  The recently used items are stored
persistently.  Thus, we won't have to deal with really long menus in
the everyday work.  I'm working on making one for colors as well. 
Please let me know if they can be improved in any way.

-Lars