Add async/await example.

Author: mattcollier

examples/async-await.rs

@@ -0,0 +1,18 @@
+use redis::AsyncCommands;
+
+#[tokio::main]
+async fn main() -> redis::RedisResult<()> {
+  let client = redis::Client::open("redis://127.0.0.1/").unwrap();
+  let mut con = client.get_async_connection().await?;
+
+  let () = con.set("key1", b"foo").await?;
+
+  let () = redis::cmd("SET").arg(&["key2", "bar"]).query_async(&mut con).await?;
+
+  let result = redis::cmd("MGET")
+    .arg(&["key1", "key2"])
+    .query_async(&mut con)
+    .await;
+  assert_eq!(result, Ok(("foo".to_string(), b"bar".to_vec())));
+  Ok(())
+}