def delete_router_interface(router, id, type)
      data = case type
        when 'port' then { 'port_id' => id }
        when 'subnet' then { 'subnet_id' => id } 
        else raise "Invalid Interface Type"  
        end
      return put_request(address("routers/" + router + "/remove_router_interface"), data, @token)
    end
def delete_router_interface(router, id, type)
      data = case type
        when 'port' then { 'port_id' => id }
        when 'subnet' then { 'subnet_id' => id } 
        else raise "Invalid Interface Type"  
        end
      return put_request(address("routers/" + router + "/remove_router_interface"), data, @token)
    end
Delete a connection between a subnet and router given either port
 or subnet ids.

 :call-seq:
   delete_router_interface(router_id, subnet_id, "subnet")
   delete_router_interface(router_id, port_id, "port")