[glade--]glademm plans for deprecated widgets (2.0)

Glademm 2.0 status:

- glademm reads old and new style project files alike.
- you can name a Version on the command line for which to generate code 
(otherwise the highest detected version is used)
- Simple (glade1) project files already generate valid gtkmm2 code (CVS 
version). But glade2 projects need more new widgets supported.

Plan:
- glademm will change the widget type on the fly (pixmap -> image) (and 
ignore old properties and the like) but this is not a good idea for 
clist/ctree -> treeview as the API is totally incompatible (IIRC, but 
perhaps I'm wrong).

Feelings:
gtkmm2 looks great. The API is much better than gtk--.
gtk2 is a breakthrough (gtk1 belongs into the trashcan).

We have work to be done, so porting gtk-- -> gtkmm2 is not highest 
priority for us. And glade-- and special widgets (gtk--addons) have to 
be ready to switch. It's a big step (a lot of old (and unmaintainable 
aka unupgradable) installations need gtk2/gtkmm2 compiles for them) and 
if the benefits would not outweight the costs we would not switch this year.