transition to main

Hello all,

we need to start promoting the packages to main so CDs can be made, and as a result
I am temporarily removing a few packages from the default xubuntu-desktop. This is so
that packages which did not get reviewed yet for security and other criteria which is a prerequisite of
being allowed to main, do not hold up the core xfce ones being transitioned.

A package in main should have all it's build dependencies satisfied in main so I removed most of the panel plugin
goodies, sylpheed, gqview and graveman. I also removed esound from the default as I think we should be ok with
plain alsa.

Jani