Updates to ubuntu-desktop set

[Jeremy Bicha]

Hi! Here are a few source packages that I believe are missing from the
ubuntu-desktop set:

- Add vte3 (vte was already in the set and is still needed for a
couple things in main)

- Restore clutter-1.0, clutter-gst, clutter-gtk, and cogl (they were
in precise but got dropped in quantal, I believe accidentally)

- And I guess now's a good time to follow up on
https://lists.ubuntu.com/archives/devel-permissions/2012-January/000322.html

Thanks,
Jeremy