[AD] Ouya controller support

[Trent Gamblin <nooskewl@xxxxxxxxxx>]

Was discussing this with Jonathan who contributed the Allegro Java->Library 
work.

On Ouya, from what I know right now, the joysticks send key events. I don't 
know yet if the second (and third and fourth) joysticks do the same with 
different keys.

My take on this is that if they do all send different keys, we don't need to 
do anything. If for some reason we can't read all of the joysticks like 
that, my idea is we should map them to ALLEGRO_JOYSTICKs. This will be a 
tiny problem on Android since the accelerometer is already using Joystick #1 
where available. That can be averted by checking the number of buttons.

Does that sound reasonable? I don't have an Ouya yet but should have mine in 
3-5 weeks.

Thanks,
Trent