unity-control-center: remove Unity stuff from display panel
unity-control-center: remove update button from info panel

We do not use update-manager. Showing the update button just confuses
users.
unity-control-center: remove Unity stuff from appearance panel
unity-control-center: remove Unity Dash legal notices

We do not have The Unity Dash.
unity-control-center: rename patch files

There is no need to keep numeric prefixes in names, because the order of
the patch queue is determined by the series file.
unity-control-center: remove user accounts panel

We support local user accounts only on personal laptops, and it has a
custom made configuration tool for the job. Having the standard
non-functional user account panel in the control center just confuses
users.