Update futures and tokio alphas

examples/server.rs

@@ -10,7 +10,7 @@ use tokio::net::{TcpListener, TcpStream};
 pub async fn main() -> Result<(), Box<dyn Error>> {
     let _ = env_logger::try_init();
 
-    let mut listener = TcpListener::bind(&"127.0.0.1:5928".parse()?)?;
+    let mut listener = TcpListener::bind("127.0.0.1:5928").await?;
 
     println!("listening on {:?}", listener.local_addr());