Added outline for graphics package

NOTE: Currently crashes on launch
Moved timing mechanism to activity controller

NOTE: Still crashes on launch
Added tank sprites
Fixed issue with paint not being properly initialized
Added common enums and interface listener
Moved occurences over to common and added to GameplayInterfaceListener
More stuff draws.  It also crashes on launch again.  :(
Basic layout draws to canvas
Added tile wall methods to GameplayInterfaceListener
Added orientation enum to common
Renamed MainActivity to GameActivity in preparation for merge with master
Merged graphics_core into master