A few audio fixes/work-arounds from Nelson

* njsf-snd:
  Whitespace cleanup
  Fix libao usage
  Cleanup some jack server interactions
  Fix typo in semaphore.h
  Fix SXEmacs semaphores so that they deal with spurius pthreads conditional variable wakeups
  Fix SoX media replay by closing and reopening stream on rewind because sox_seek is broken
  Fix some synchronization issues. Improve audio job debug output