Fix actix-http examples (#1259)

Fix actix-http examples

actix-http/examples/echo.rs

@@ -7,7 +7,8 @@ use futures::StreamExt;
 use http::header::HeaderValue;
 use log::info;
 
-fn main() -> io::Result<()> {
+#[actix_rt::main]
+async fn main() -> io::Result<()> {
     env::set_var("RUST_LOG", "echo=info");
     env_logger::init();
 
@@ -37,4 +38,5 @@ fn main() -> io::Result<()> {
                 .tcp()
         })?
         .run()
+        .await
 }

actix-http/examples/echo2.rs

@@ -19,7 +19,8 @@ async fn handle_request(mut req: Request) -> Result<Response, Error> {
         .body(body))
 }
 
-fn main() -> io::Result<()> {
+#[actix_rt::main]
+async fn main() -> io::Result<()> {
     env::set_var("RUST_LOG", "echo=info");
     env_logger::init();
 
@@ -28,4 +29,5 @@ fn main() -> io::Result<()> {
             HttpService::build().finish(handle_request).tcp()
         })?
         .run()
+        .await
 }

actix-http/examples/hello-world.rs

@@ -6,7 +6,8 @@ use futures::future;
 use http::header::HeaderValue;
 use log::info;
 
-fn main() -> io::Result<()> {
+#[actix_rt::main]
+async fn main() -> io::Result<()> {
     env::set_var("RUST_LOG", "hello_world=info");
     env_logger::init();
 
@@ -24,4 +25,5 @@ fn main() -> io::Result<()> {
                 .tcp()
         })?
         .run()
+        .await
 }