* components/tree/nautilus-tree-expansion-state.h,
	components/tree/nautilus-tree-expansion-state.c: New files
	implementing the NautilusTreeExpansionState class, a class to
	track the expansion state of various nodes in the tree, and
	save/load it to/from GConf.
	* components/tree/nautilus-tree-model.h,
	components/tree/nautilus-tree-model.c
	(nautilus_tree_model_stop_monitoring_node_recursive): New function
	to stop monitoring a node and any children of it's that you may be
	monitoring all at one go.
	(nautilus_tree_model_stop_monitoring_node): Disconnect signal
	handlers from the proper object (D'oh!) and avoid disconnecting
	more than once if you stop monitoring more than once (D'oh!).

	* components/tree/nautilus-tree-view.c:
	(nautilus_tree_view_insert_model_node,
	nautilus_tree_view_remove_model_node,
	nautilus_tree_view_update_model_node),
	nautilus_tree_view_initialize, nautilus_tree_view_destroy,
	tree_expand_callback, tree_collapse_callback): Track expa...