[ubuntu-studio-devel] Installer changes, and other last minute changes

[Kaj Ailomaa]

ubuntustudio-live has now replaced ubuntustudio-live-settings on the
DVD. The switch happens during next build of the ISO.
What this means is that the installer now has an additional page (a
ubiquity plugin)
We need to test the installer plugin, which allows us to choose from
ubuntustudio packages, and report bugs.

Additionally, I added Rui's latest work to our
ubuntustudio-audio-plugins meta: synthv1, drumkv1 and samplv1.