* libnautilus-extensions/nautilus-global-preferences.h:
	Add preferences for default manual layout support.

	* libnautilus-extensions/nautilus-global-preferences.c:
	(default_icon_view_sort_order_or_manual_layout_changed_callback),
	(nautilus_global_preferences_initialize):
	Use different enumerations for icon view and list view default
	sort order since only icon view supports manual layout.  Add
	entries for default manual layout preference.  Add proxy
	preference for both icon view sort order and manual layout so that
	it can be presented to the user as one choice and thus just one
	menu.  This also matches the view menu.

	* libnautilus-extensions/nautilus-preferences-item.c:
	(preferences_item_create_enumeration_list),
	(preferences_item_create_enumeration_menu):
	Add support for separators in string pickers.

	* src/file-manager/fm-icon-view.c:
	(get_default_directory_manual_layout),
	(fm_icon_view_real_get_directory_auto_layout),
	(fm_icon_view_real_set_directory_auto_layout),
	(fm_icon_view_reset_to_defaults),
	(default_use_manual_layout_changed_callback),
	(fm_icon_view_initialize):
	Add support for a default "use manual layout" preference.

	* src/nautilus-preferences-dialog.c:
	Make the default sort order preference use the proxy prefernece
	instead of the real one.