Edubuntu Edgy CD diet

The Edubuntu CDs are constantly oversized due to the fact that is ships GNOME and KDE applications and thus has the backend libraries as well as the translations for both desktops.

This spec will determine the possibilities to reduce the CD size by checking the following options among others that might come up during BOF discussions:

 * review possibility to replace kdeedu with gnome apps or if thats not possible, create kdeedu specific langpacks to at least reduce the oversizedness a bit

 * Replace firefox with epiphany in edubuntu (depends on xulrunner inclusion in the distro), this has not only the advantage of reducing the size, but also enables us to use the gnome kiosk mode through pessulus/sabayon