Add facilities for D-Bus interface annotations and use them to mark the old D-Bus interfaces as deprecated.
* mandos (dbus_interface_annotations): New decorator. (DBusObjectWithProperties._is_dbus_property): Removed. All callers changed. (DBusObjectWithProperties._is_dbus_thing): New; generalized version of "_is_dbus_property". (DBusObjectWithProperties._get_all_dbus_properties): Removed. All callers changed. (DBusObjectWithProperties._get_all_dbus_things): New; generalized version of "_get_all_dbus_properties". (DBusObjectWithProperties.Introspect): Also add interface annotation tags. (AlternateDBusNamesMetaclass.__new__): Also copy interface annotations. Add "deprecated" annotation on old interface. (ClientDBus._foo): New interface annotation to mark non-compliance with the standard property change signal interface. (MandosDBusService): Inherit from DBusObjectWithProperties to get interface annotation support. (MandosDBusService._foo): New interface annotation to mark non-compliance with the standard property change signal interface.