Joystick support

[Beeblerox]

for the help see:

• HaxePunk
• Joshua'a article and sample project http://www.joshuagranick.com/blog/2012/01/25/joystick-and-gamepad-support-for-nme/

[Beeblerox]

I've added basic Joystick functionality. For next possible improvements see issue #89

[impaler]

To get multiple axis from one gamepad it looks like we might need to rethink handleAxisMove in FlxJoystickManager to support multiple joystick axis.

Related http://www.nme.io/community/forums/general-discussion/right-analogue-stick-xbox-360-gamepad/

Also would need to see if this can be done in an "easy" way with multiple types ps3/xbox as the event array ids and buttons could be different.

[Beeblerox]

@impaler or we can create joystick configuration screen

[Beeblerox]

@impaler I've just tested my cousin's gamepad (which is very similar to playstation's gamepad, at least i think so - it is Logitech cordless rumblepad 2) and having access to joystickevent.axis array seems enough, since it contains info about both joysticks on controller (first two - about left, and other pair of values - for right joystick)

[gamedevsam]

The thing I wonder is if the joystick and button data is the same for similarly positioned buttons on different controllers. So for example, if 'A' and 'X' on Xbox and PS3 controllers send out the same key code. If they did then we wouldn't have to do anything special, but if not we need to figure out a solution for being able to remap keys and axis easily.