Dia bonobo component.

[Alexander Larsson]

Ok. I've commited the first version of a Dia bonobo component.
It's a bit rough, but it works. No persistance yet though.

Both the gnome and the Gtk+ version seems to work, but the gnome version
gets a Critical error on startup because gnome is initialized twice. I
didn't find a way to avoid this.

There is also some major suckage in the code that disables some menu
entries for embedded mode. Don't look at it, it will hurt your eyes.

/ Alex