codec: implemented libjpeg module

Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>
live555: retrieve RTSP track languages from SDP

First for the "a=lang:" session attribute, then for each subsession
look for the same attribute, and use the session attribute if none
was found.

Signed-off-by: Jean-Baptiste Kempf <jb@videolan.org>