Original commit message from CVS:
* ext/ogg/gstoggmux.c: (gst_ogg_mux_init),
(gst_ogg_mux_next_buffer), (gst_ogg_mux_buffer_from_page),
(gst_ogg_mux_push_page), (gst_ogg_mux_get_headers),
(gst_ogg_mux_set_header_on_caps), (gst_ogg_mux_send_headers),
(gst_ogg_mux_loop):
Use stream caps to setup the initial pages in the ogg stream.
Correctly set the streamheader caps on the srcpad.