Version A_01.1

+ Added 'AIR_DECEL' variable to player to control air deceleration (if
ever desired)
+ Added more comments to code
+ Added base for game menu functionality (currently does nothing)
* Renamed 'Platform' to 'Wall' for clarity in future updates
* Similarly renamed 'run2' to 'animate' for future clarity
* Fixed bug
* Made window larger
+ Added variables to control window size