* Allow editing the StateSet of the Drawables!

* Add methods in the matrix attribute editor to build up common matrices
 like ortho, perspective, translations, rotations, etc.

* GTK-only version to port it to windows

* Implement support for more state attributes

* Draw Axis on the screen for each transform operation to allow doing it in
  all or only one axis

* Fix a bug with make_current when more than one editors open

* Implement a model library both global (in /usr/lib/osgedit) and local (in
  ~/.osgedit) so that user can have their models organized.
