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.