This update allows for much more flexibility in the HRTF data. It also allows
for HRTF table file names to include "%r" to represent the device's playback
rate (e.g. if you set hrtf-%r.mhr, then it will try to use hrtf-44100.mhr or
hrtf-48000.mhr depending if the device's output rate is 44100 or 48000,
respectively).
The makehrtf utility has also been updated to support more options and input
file formats, as well as the new mhr format.
The data is based on the KEMAR HRTF data provided by MIT, which can be found at
<http://sound.media.mit.edu/resources/KEMAR.html>. The compact measurements
were used. See hrtf_tables.inc for more information.
The filter is only available for stereo output, using a 44100hz playback rate.
Note also that it currently only applies to mono sounds, and the cf_level and
head_dampen config options are ignored while it is active.
