Playback sync; OSS license

• When playing a file, the time reported by Au_GetTimeInPlayback() is the time in the track, not the elapsed real time.
• Licensed under the Apache license 2.0.

It plays a WAV file!

It integrates PortAudio and libsndfile well enough that it can play a 16-bit WAV file exported from Audacity. There's a long way to go, but this is a very good start!