Restarting development: Audio

First thing we'll do is handle how audio is loaded. The current game starts by loading in every single song that will be used, which isn't a problem in Windows, but is on Android. The loading times can be as long as 60+ seconds.

The benefit is that, once playing, the loading is very fast. However, compared to adding 5 seconds per loading screen, I'd like for the game to start up a bit faster.

Hence I need to overhaul how audio is loaded and unloaded (the songs), but also the button and other sound effects.

Updates to follow.