[openal] OpenAL Soft now on GitHub

[Chris Robinson]

I've set up another repository for OpenAL Soft on GitHub:

https://github.com/kcat/openal-soft

This repo will act as a mirror to the normal repo at repo.or.cz (both 
will be kept up to date). What this means, among other things, is that 
OpenAL Soft now has an issue tracker where I can better keep track of bugs:

https://github.com/kcat/openal-soft/issues

If you've previously reported a bug that hasn't yet been fixed, feel 
free to create a new issue about it. I will also accept pull requests, 
although I do still prefer patches so I can make sure it doesn't break 
the build before putting it in the repo (GitHub has something to test if 
a pull request still builds before merging AFAIK, but I haven't read up 
enough on that yet).