Applied patch from bug #947

	Applied patch from bug #947

	* clutter/clutter-stage.c (clutter_stage_get_default): Don't grab
	the floating reference when creating the default stage. The stage
	manager will take a reference to it so it will behave as any other
	stage.
	(clutter_stage_new): Don't take the floating reference to the new
	stage but let the stage manager keep it instead.

	* clutter/clutter-stage-manager.c
	(_clutter_stage_manager_add_stage): Take a reference to the stage
	when it is added to the list.
	(_clutter_stage_manager_remove_stage): Unref the stage when it is
	removed from the list.
	(clutter_stage_manager_dispose): Keep track of the 'next' pointer
	as a separate variable so we can cope when the stage being
	destroyed removes itself from the list as the list is being
	iterated.

	* clutter/clutter-actor.c (clutter_actor_destroy): Take a
	reference at the beginning of the function even if there is no
	parent container so that overall the reference count is not
	changed when the actor is unref'd again at the bottom of the
	function. Previously it would have a net effect of leaving the
	reference count alone unless it is a top level actor in which case
	it would unref it.