Remove reference to the unsupported master format from ffserver.conf.

Originally committed as revision 14675 to svn://svn.ffmpeg.org/ffmpeg/trunk

doc/ffserver.conf

@@ -84,7 +84,6 @@ Feed feed1.ffm
 # asf        : ASF compatible streaming (Windows Media Player format).
 # swf        : Macromedia Flash compatible stream
 # avi        : AVI format (MPEG-4 video, MPEG audio sound)
-# master     : special ffmpeg stream used to duplicate a server
 Format mpeg
 
 # Bitrate for the audio stream. Codecs usually support only a few