[RFC] Adding an OpenAL DLL thunk

[Stefan Dösinger]

I'll give it a try with my games. The old thunk from a while ago already 
worked very will with those games.

OpenAL seems to have an extension system like opengl. If there is a function 
that returns an extension string we'll want to remove any extension our thunk 
doesn't know about. However, I can't find any such function, but I only did a 
very quick search