Function resp_async::listen_and_serve

pub fn listen_and_serve<F, U, T>(
    addr: &SocketAddr, 
    f: F
) -> impl Future<Item = (), Error = Error> where
    F: Fn(&mut PeerContext<T>, Value) -> U + Clone,
    U: IntoFuture<Item = Value, Error = Error> + Send + Sync,
    T: Default,