HTTP Client with KeepAlive

[yoshuawuyts]

Moving the conversation from #1 here; @dignifiedquire proposed we build an HTTP client like so:

async fn main() -> throws {
    let tcp_stream = net::TcpStream::connect("127.0.0.1:8080").await?;
    let (tcp_reader, tcp_writer) = &mut (&tcp_stream, &tcp_stream);

    let http_stream = client::connect(tcp_reader);

    // lets make 10 requests, with the same connection
    for i in 0..10 {
        // Send a response
        let body = Body::from(format!("hello chashu {}", i));
        let mut req = client::encode(Request::new(body));
        tcp_writer.write_all(req).await?;

        // read the response
        let res = http_stream.next().await?;
        println!("Response {}: {:?}", i, res);
    }
}

[yoshuawuyts]

done!