Merge remote-tracking branch 'cehoyos/master'

* cehoyos/master:
  Mention in the documentation that fieldmatch needs cfr input.
  Use v4l2 input format automatically if filename starts with "/dev/video"
  Print a warning if a subtitle demuxer changes utf16 to utf8.
  Do not set the lame quality if the user didn't request it.

Merged-by: Michael Niedermayer <michaelni@gmx.at>