[mythtv] nuv header format...

[Chris Petersen]

ok, so I'm hoping to be all ready to parse the nuv file header info by
the time that mythtranscode is updated for audio sync issues...  
however, being that I'm pretty clueless when it comes to C data
structures (especially in files), I need a little help...

I've cracked open libs/libmythtv/format.h and can grab the rtfileheader
stuff just fine, but I can't figure out where to continue looking in
order to find the audio sampling rate (or any other info that I might
want to pull out).

-Chris