cleanup

Conflicts:
	libeplayer3/include/aac.h
	libeplayer3/include/output.h
	libeplayer3/include/playback.h
	libeplayer3/output/writer/writer.c
	libeplayer3/playback/playback.c
libeplayer3: remove debugging output; abort if neither an audio nor a video stream is available

Conflicts:
	libeplayer3/container/container_ffmpeg.c
libeplayer3: initalize AVSubtitle

Conflicts:
	libeplayer3/container/container_ffmpeg.c