Since the wayland protocol doesn't currently provide a way to
retrospectively query the interfaces that get notified when a client
first connects then when using a foreign display with Cogl then we also
need api for telling cogl what compositor and shell objects to use. We
already had api for setting a foreign compositor so this patch just adds
api for setting a foreign shell.
This patch also adds documentation for all the wayland specific apis.
Reviewed-by: Neil Roberts <neil@linux.intel.com>
14ddbd980b