panels failed to load.

	* libnautilus-private/nautilus-directory-metafile.c:
	(die_on_failed_activation): Give better error messages.
	(get_factory): Check the ev result from oaf_activate_from_id
	rather than relying on getting NIL when it fails.
	(open_metafile): New helper function.
	(get_metafile): Don't complain if the open call fails the first
	time, and re-get the factory and retry before doing a g_error.