Magnetize Optimization 1

Code changes:
+ General optimization: some of the game logic used to run all the time, only runs when you're near. 
+ Fixed some memory leaks caused by particles.
+ Level 12 Boss sounds now stop when you die.

Cosmetic changes:
+ Added a couple new sprites.
+ Application surface was doubled, now boxes won't appear cut in half.
+ Doors that didn't look like doors now look appropriately.

Other:
+ Game is now a zip file instead of an installer.