Fix a number of multi-user bugs

-Expose User Interface for non owner users.  Every option in user
 interface is multi-user compatible, except halo, which has to be
 disabled for non owner users :(
-Power sounds is not multi-user compatible, fix it!
-Reorganize and general cleanup

 This is a big derp :)

Signed-off-by: Paul Beeler <sparksco@gmail.com>