message: feat(server): remove unneeded Send + Sync from Server
  Http and Server placed Send + Sync bounds on NewService implementations which
  were not actually required given tokio's event loop model. Remove them to reduce
  limitations on end users of hyper.
diff: @@ -96,8 +96,7 @@ impl<B: AsRef<[u8]> + 'static> Http<B> {
  /// The returned `Server` contains one method, `run`, which is used to
  /// actually run the server.
  pub fn bind<S, Bd>(&self, addr: &SocketAddr, new_service: S) -> ::Result<Server<S, Bd>>
  - where S: NewService<Request = Request, Response = Response<Bd>, Error = ::Error> +
  - Send + Sync + 'static,
  + where S: NewService<Request = Request, Response = Response<Bd>, Error = ::Error> + 'static,
  Bd: Stream<Item=B, Error=::Error>,
  {
  let core = try!(Core::new());
  @@ -378,8 +377,7 @@ impl<T, B> Service for HttpService<T>
  }
  impl<S, B> Server<S, B>
  - where S: NewService<Request = Request, Response = Response<B>, Error = ::Error>
  - + Send + Sync + 'static,
  + where S: NewService<Request = Request, Response = Response<B>, Error = ::Error> + 'static,
  B: Stream<Error=::Error> + 'static,
  B::Item: AsRef<[u8]>,
  {
  