Add support for native Android gamepad

[GoogleCodeExporter]

What steps will reproduce the problem?
1. Gamepad support is missing.

What version of the product are you using? 

1.91

Please provide any additional information below.

Further to my comments in Issue #19 
(http://code.google.com/p/quake2android/issues/detail?id=19), native Android 
gamepad support would be a godsend. Hopefully this could be achieved by 
leveraging Quake 2's support for gamepads/joysticks. More info of my workaround 
is in Issue #19 linked above, but it surely isn't ideal.

Original issue reported on code.google.com by scar45 on 5 Oct 2012 at 6:22