delt(host|net, gw|dev)

def delt(self, *args, **kargs):
        """delt(host|net, gw|dev)"""
        self.invalidate_cache()
        route = self.make_route(*args, **kargs)
        try:
            i = self.routes.index(route)
            del(self.routes[i])
        except ValueError:
            warning("no matching route found")