Pull Asset Loading out into its own state and file

This state is super simple, we will just load all our assets like we
did in the preload() function in the previous tutorial.
Add Menu Functionality in menu.js

If game has been played, last score will be shown.

Press Start to play
Add the Play State to manage all game mechanics

pulled out of main.js
Add Game.js

Initialize phaser, and set global variables

initialize all game states
Deleted main.js

All files moved into separate files.

no longer necessary
Ummmm

Hmmmm
Not sure what I did
Revert ad06e62..89a4dd4

This rolls back to commit ad06e6279ca030f5c99824badd3bbe55a9d5dee6.