Update the way audio is played

This is kind of an overhaul of the audio system.  Before all of the
memory was staically allocated.  This meant that more memory was being
allocated than actually used.  Sounds will now only allocate what they
need.  The changes also allow multiple sounds to play at once.  Right
now the whole game will "chug" whenever the main audio buffer needs to
be updated.  I'll look into that further tomorrow.
Remove unused function call
Initialize AudioController and add menu loop

This will loop some music during the main menu.  Once the game is
started the loop will be removed from memory.