Updated Ubuntu Installer to 21.10
Updated Ubuntu Installer to 21.10

* Switched to Gnome
* Removed a few packages I don't need anymore
* Removed all dependencies on third-party repos for non-FOSS software
  like Discord and Slack
* Removed Wire and Matrix messengers because these work exactly the same
  on the browser versions
* Added signal-desktop via its own repositories
* This is going to be used on a Lenovo IdeaPad Duet 3i with a Celeron
  N4020 and 4GB of RAM, so the expectation is that most software would
  run off the browser.

mahtuag/DistroSetup,mahtuag/DistroSetup