message: Fix http server example.
diff: @@ -25,13 +25,19 @@ fn serve(stream: Arc<TcpStream>, mut all: Vec<u8>) {
  return;
  }
  };
  - if let Some(pos) = s.find("\r\n\r\n") {
  + if let Some(_pos) = s.find("\r\n\r\n") {
  + let body = format!(
  + "Hello, world!\n",
  + ).into_bytes();
  + let stream = stream2.clone();
  stream2.write_all_async(
  format!(
  - "HTTP/1.0 200 OK\r\nContent-Type: text/plain\r\n\r\nYour headers: \n\n{}\n",
  - ::std::str::from_utf8(&all[..pos]).unwrap()
  + "HTTP/1.1 200 OK\r\nContent-Type: text/plain\r\nConnection: close\r\nContent-Length: {}\r\n\r\n",
  + body.len()
  ).into_bytes(),
  - |result| {}
  + |_| {
  + stream.write_all_async(body, |_| {});
  + }
  );
  } else {
  schedule(|| serve(stream2, all));
  