Moved dialog boxes to inside the PhysicsWorld, implemented _upgrades for replacement of player attributes.

Signed-off-by: fad4470 <fad4470@rit.edu>
Lotsa stuff:
-Implemented player attributes in _upgrades dictionary
-Implmeneted James' first 3 levels
-Added player animations
-Added simple controls screen
-Added escape key to return to menu
-Altered wall-jumping by James' request. Pressing the key off the wall also jumps.
-Altered wall-sliding by James' request. Pressing towards the wall is required to stick to it.
-Put the dialog box in the PhysicsWorld clip

Signed-off-by: fad4470 <fad4470@rit.edu>