docs: add missing types
docs: add missing types

https://bugzilla.gnome.org/show_bug.cgi?id=750764

surround-io/gst-rtsp-server,barisdemiray/gst-rtsp-server,barisdemiray/gst-rtsp-server,surround-io/gst-rtsp-server,barisdemiray/gst-rtsp-server,thaytan/gst-rtsp-server,thaytan/gst-rtsp-server,surround-io/gst-rtsp-server,thaytan/gst-rtsp-server