This script contains contants to be used by other scripts, including:

• numbers sent to the Eye Tracker parallel port (i.e. event codes). 
• enumerations 
• default categories 
• Gamepad Button assignments 

- Created ~5/2011 by DJ.
- Updated 6/8/11 - added FOLLOW
- Updated 3/13/12 - added CATEGORIES, CATEGORYSTATES, IS3DCATEGORY, TARGET/DISTRACTOR/UNUSED, and CUBBYSIZE
- Updated 11/22/13 - simplified
- Updated 12/17/13 - added GAMEPAD_BUTTONNAMES, comments