[incompat,new_func,->RELENG_1_2] add disconnect_by_portref_connector_name() and disconnect_by_portref_connector_id(), disconnect_all_by_ref(). refs #3400
[incompat,new_func,->RELENG_1_2] add disconnect_by_portref_connector_name() and disconnect_by_portref_connector_id(), disconnect_all_by_ref(). refs #3400