Joystick Support

Problematic Points:
* ViewHat as Buttons don't work. This means you can't use the quickbuttons that are typically there
*  XBox Morrowind separates "Use" and "Cast". PC combines them. Not a major problem, probably an improvement
* Implementing SDL_GameController should be done at some point, it handles game controllers better then SDL_Joystick, allows for more verbose button names ("Start" as opposed to "Button 10").
* Removing/Adding controllers which the program is running is problematic. Not sure why, but it worked before I switched development computers, perhaps some sort of SDL update?
Bug number or description?