Adjust defaults
Fix sloppy KMQuake II code

-No longer look for the cursor model every time it attempts to draw it
Add support for loading controller mappings from a file

By default it attempts to load two files: gamecontrollerdb.txt and
controllers.cfg: controllers.cfg will ship in vrquake2.pk3 as the
default load set which can be overwritten by adding gamecontrollerdb.txt
to baseq2 directory. See https://github.com/gabomdq/SDL_GameControllerDB
for more information on the file format.