major overhaul of the home screen and sidebar button editor.  trying to make the code as reusable as possible.
now you can add sidebar buttons to launch anything you like.  as well as home screen buttons.
drag drop works on each side. later i'll get side to side working.  and hopefully between screens too.
sorry about the db, but it needs to be upgraded and this update will remove any existing home screen buttons configured.

Signed-off-by: Eric Friesen <efriesen@gmail.com>
new apk with button editor changes

Signed-off-by: Eric Friesen <efriesen@gmail.com>