Deletes old test game
Demo game is now playable
Updates demo game with steering and changes in sprites
Fixes smaller bugs in sprites
Refactor class names in game demo
Strips Box2D from game
Fixes ordering in game node
Adds frameRate property to SpriteBox and improves update methods.
Fixes node to box transformations for hit tests
Fixes minor code issues
R=abarth@chromium.org
Review URL: https://codereview.chromium.org/1179333002.