This gets the data about which apps are installed from the ContentProvider
that pserwylo recently added for data about "Installed Apps" and presents
a list view for the user to select from by touching each line. Then if the
user chooses "Update Repo", it will regenerate the local repo based on the
current selection. It will always include FDroid in the local repo.
fixes#3232https://dev.guardianproject.info/issues/3232
refs #3204https://dev.guardianproject.info/issues/3204