Release Candidate 2

Bugfixes:
Put a time limit on door script audio. If the player entered the collision zone multiple times the audio would play a whole bunch of times.
Explosion was being set off for each collision box.
Modified Player1's Polygon collider and reduced the vertices to prevent it from getting stuck in overlapped colliders
Fixed Level 2's checkpoints. Both had collision boxes that were on the wrong side of the door.