Factored out Engine/App parts.
Moved INIT constants back in.
Removed debugging calls.
Changed Keycode values to Codepoints.
Changed FFI enums to EnumerableConstants
Moved INIT into Mixer file, added missing contants.
Implemented Chunk::load_wav,#play, and #playing?
Got rid of debug messages for now.
Fixed approvals failing because of Alpha problems.
And fixed wrong paramater type in SDL_SetColorKey