Moves some files around.

Moves games.js from engine/ to game/
Moves stateMachine.js from engine/systems/ to engine/
Adds a debug box sprite creation method to Graphics
A sweet physics demo
Touching up this silly demo.
Moves games.js back into engine/ so merging with master won't be a pain.

Tweaks some physics values (gravity, world size) to make demo more
interesting.
Less hacky physics world size... Not final solution
Final tweak to physics demo.

Made bgColor sweet looking.
Physics bodies can set their initial rotations.
In the demo, fixed boxes will be wider than dynamic boxes.
Adds 'randomInteger' and 'randomReal' to utils.js
Warm the physics sim before ticking the game
Better sprite drawing

Fixes bug in utils.js that prevented the use of js.defaults() without a
second parameter.

Fixes bug when creating box sprites that caused them to be too large.
Fixes bug in physics when creating box shapes that caused them to be too
large.

Adds debug circle sprite to graphics.js, makes box and circle drawing
share code.
Circles!

Adds circle shapes to physics.

Mainly I want to use circles as debug graphics, but why not add them to
physics as well?
Improves debug sprites
Tweaking some silly shit before sleep.
Merge branch 'dev/box2d-world-from-tiles'

Conflicts:
	client/src/engine/game.js
	client/src/engine/graphics.js