remove duplicated parser, people who pass random gibblets of the bitstream into the decoder will have to pass it through a AVParser like for all other codecs too
remove silly internal buffering architecture (removes 1 memcpy() of the bitstream)
mp3on4 and mp3adu untested


git-svn-id: file:///var/local/repositories/ffmpeg/trunk@6098 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b