* Remapping GUI V2 - initial commit
* Unmap button with escape key
* Allow combination inputs
* Use separate class for SDL event signals so that i can work with the SDL window event loop
* Automatically pause game when GUI open to better manage event queue
* Move sd;_gamepad_added event from remap object to GUI object to avoid conflicts with sdl window
* Use signals on button/trigger to release to make GUI more responsive
* pause game while KBM window is open for consistency
* don't check gamepad when game is running to avoid conflicts
* Block all other sdl events instead of pausing game, automatic parse inputs after saving
* Don't block window restored or window exposed cases
* Properly exit event loop thread on exit
