Removed OpenAL and GLFW3 dependencies on building.
Reviewed platforms and flags

Inspired by #504.
Instead of requiring the user to do PLATFORM_ANDROID #ifdefery,
have the android_main entry point exported by raylib and call
the user-defined main. This way many games could (in theory)
run unmodified on Android and elsewhere.

This is untested!

Some people might find this handly

Updated to new audio system

This game was developed for King GameJam 2015