Always add the user to the 'sudo' group as it's been around
since at least Ubuntu 10.04. In addition make the user part
of the admin group until 12.04 where it's been removed.
Also fix a minor layout issue with devttydir.
Signed-off-by: Serge Hallyn <serge.hallyn@ubuntu.com>
Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>