Refactored assets loading
Fixed issue where the shell was alive forever!
Fixed the bug where arrow keys would propagate to the browser.
delta now propagates to all the update functions
Merge branch 'refactor_asset_loading'
Separated the Tank to a hull and a turret sprites
added a barrel object and an explosion
simple collision manager works
fixed some things after the assets change
exploaded animation is now loaded with the preloaer
Merge branch 'explodingBarrel'
Merge remote-tracking branch 'origin/master' into add_hp_bar
Added hp bar to tank
Merge branch 'add_hp_bar'
Added explosion sound effect
Replaced collision manager and separated the barrel from the explosion
Fixed the explosion graphics
Added barrel placement and added evnted API to state.
Merge branch 'master' into gh-pages