Refactored Engine to EngineSingleton. Experimental code updates to
follow
Committing code changes for historical purposes
Full codebase for the Singleton Experiment
Status: successful
Notes: 
Engine is now a singleton. No classes require an Engine instance to run,
and any time they need to get information from the main Engine they do
so through convenience methods - largely, this only relates to adding,
removing and setting scenes.

Changed: EngineSingleton to Engine - the codebases shouldn't differ.
Added Title to Menu's.
Added CreateSaveScene - new game menu
Added in dynamic item generation to CreateSave and LoadMenu scenes. They
now look for files of pattern slotX.dat, where X is a number 1 to 3 in
/data/save/ (/data/save/slot1.dat)

Fixed bug in Menus where up arrow would cycle items rather than one at a
time.
More changes to the preloader and keyboard.
Updated the way Keyboard logs keys - no longer has defaults
Menus now have a background, too
Next commit will see Audiologist transition to being a Singleton and
menu ambience
Audilogist is now a singleton
Calls take the form of Audiologist.loadSound(file,name),
Audiologist.play() and Audiologist.playInstance();

Updated defaults to return a uri for sounds
Updated BaseScene/TestAudiologist to use new Audiologist calling
convention
Updated PreloaderScene to start the menu music

Added Menu Ambience mp3.
MainMenuScene disposes Audiologist before killing the engine.
Renderer can now dispose itself
GameScene calls upon Renderer's disposal when dying
SceneGraph calls disposal on all disposable screens when dying
Engine calls disposal on SceneGraph during kill phase.
Committing latest updates
Preloader scene preloads scripts now!
Minor fixes to Cache
Committing changes to preloader.
Preloader really needs a auto loader rather than hand writing
everything....

Also got lots of sounds and stuff in this one.
folder changed
removed unnecessary imports