Updater: No need to install every update

* Apparently users are not aware that they don't have to install every
  update we ever released (weeklies) after they have skipped some due
  to various reasons
* Since we are providing full installation packages, remind the user that
  it's ok to only ever choose the newest one

Change-Id: I70f9acd70344f36aaae7e45b848f6bcb7a8b3c0f