We can enumerate Winmm devices
Complete, basic winmm backend
Fix sleeping in the winmm backend
Set the 3D example's mixahead and buffer size to soemthing sensible
Add a sleep to the winmm backend to give the mixer a chance to get ahead
Properly initialize the atomic variables common to all backends
Merge branch 'master' into audio_backends
Merge branch 'master' into audio_backends
Properly fixed winmm warmup by globally moving startup_hook