* Removes Linux-specific joystick handling
* Adds cross-platform GLUT joystick handling; Caveats:
- GLUT is not robust to joystick hot plugging like my old Linux-specific code was. (Fix should be made in the
GLUT driver and pushed upstream if we really care)
- Deprecated X11 renderer now can only use keypad joystick
* Use defines instead of magic numbers in a bunch of places
* Remove deprecated ii_keymaps and only use iie_keymaps
* Allow keypad corners for emulated joystick
* Deprecate "lazy" color modes
* Allow setting speaker sound volume
* Make Joystick code more generic (future support of touch input)
* Deprecate setting emulator mode (//e is ascendant)