ext/divx/gstdivxdec.c: Downgrade priority. We prefer ffdec_mpeg4.

ext/divx/gstdivxdec.c: Downgrade priority. We prefer ffdec_mpeg4.

Original commit message from CVS:
* ext/divx/gstdivxdec.c:
Downgrade priority. We prefer ffdec_mpeg4.
* ext/faad/gstfaad.c: (gst_faad_srcgetcaps), (gst_faad_srcconnect),
(gst_faad_chain), (gst_faad_change_state):
Fix capsnego. Doesn't work for some sounds because we don't have
a 5:1 to stereo element.
* ext/xvid/gstxvid.c: (plugin_init):
Add priority.
* sys/oss/gstosssink.c: (gst_osssink_init), (gst_osssink_chain),
(gst_osssink_change_state):
Add discont handling.