add code to test H2 speed

I currently get about 1MB/s, which is ways too slow (must be a bug)?

src/bin/h2server.rs

@@ -0,0 +1,65 @@
+use failure::*;
+use futures::*;
+
+// Simple H2 server to test H2 speed with h2client.rs
+
+use tokio::net::TcpListener;
+
+use proxmox_backup::client::pipe_to_stream::*;
+
+pub fn main() -> Result<(), Error> {
+
+    start_h2_server()?;
+
+    Ok(())
+}
+
+pub fn start_h2_server() -> Result<(), Error> {
+
+    let listener = TcpListener::bind(&"127.0.0.1:8008".parse().unwrap()).unwrap();
+
+    println!("listening on {:?}", listener.local_addr());
+
+    let server = listener.incoming().for_each(move |socket| {
+
+        let connection = h2::server::handshake(socket)
+            .map_err(Error::from)
+            .and_then(|conn| {
+                println!("H2 connection bound");
+
+                conn
+                    .map_err(Error::from)
+                    .for_each(|(request, mut respond)| {
+                        println!("GOT request: {:?}", request);
+
+                        let response = http::Response::builder().status(http::StatusCode::OK).body(()).unwrap();
+
+                        let send = respond.send_response(response, false).unwrap();
+                        let data = vec![65u8; 1024*1024];
+                        PipeToSendStream::new(bytes::Bytes::from(data), send)
+                            .and_then(|_| {
+                                println!("DATA SENT");
+                                Ok(())
+                            })
+                    })
+            })
+            .and_then(|_| {
+                println!("H2 connection CLOSE !");
+                Ok(())
+            })
+            .then(|res| {
+                if let Err(e) = res {
+                    println!("  -> err={:?}", e);
+                }
+                Ok(())
+            });
+
+        tokio::spawn(Box::new(connection));
+        Ok(())
+    })
+    .map_err(|e| eprintln!("accept error: {}", e));
+
+    tokio::run(server);
+
+    Ok(())
+}