gst/auparse/gstauparse.c: - Document all audio encoding we can encounter from Solaris 9 headers and libsndfile inform...

Original commit message from CVS:
* gst/auparse/gstauparse.c :
- Document all audio encoding we can encounter from Solaris 9
headers and libsndfile information.
- Increase max. rate from 48000 to 192000 (to match other elements)
- Don't try to play junk data between header and samples