[PROPOSAL] Remove 'joystick', 'gamecontroller', etc from default profile save name

[jsbackus]

The resolution to issue #70 exposes the 'sub-extension' AM adds to the default save name when saving profiles. I don't see any benefit to keeping this 'sub-extension'. Controller type is stored inside the file, so this wouldn't affect functionality. Comments?

[Keith94]

I agree, for simplicity's sake you should remove the .gamecontroller from the file name and just leave .amgp as the extension.