Log Message:
Add SDL2_sound version 2.0.1 to pkgsrc-current

SDL2_sound is a library that handles the decoding of several popular sound file
formats, such as .WAV and .MP3.  It is meant to make the programmer's sound
playback tasks simpler.

The programmer gives SDL2_sound a filename, or feeds it data directly from one
of many sources, and then reads the decoded waveform data back at her leisure.

If resource constraints are a concern, SDL2_sound can process sound data in
programmer-specified blocks.  Alternately, SDL2_sound can decode a whole sound
file and hand back a single pointer to the whole waveform.  SDL2_sound can also
handle sample rate, audio format, and channel conversion on-the-fly and
behind-the-scenes, if the programmer desires.