guide update

guide/src/qs_3_5.md

@@ -1,5 +1,33 @@
 # Server
 
+[*HttpServer*](../actix_web/struct.HttpServer.html) type is responsible for 
+serving http requests. *HttpServer* accept applicaiton factory as a parameter, 
+Application factory must have `Send` + `Sync` bounderies. More about that in 
+*multi-threading* section. To bind to specific socket address `bind()` must be used.
+This method could be called multiple times. To start http server one of the *start*
+methods could be used. `start()` method start simple server, `start_tls()` or `start_ssl()`
+starts ssl server. *HttpServer* is an actix actor, it has to be initialized
+within properly configured actix system:
+
+```rust
+# extern crate actix;
+# extern crate actix_web;
+use actix::*;
+use actix_web::*;
+
+fn main() {
+    let sys = actix::System::new("guide");
+
+    HttpServer::new(
+        || Application::new()
+            .resource("/", |r| r.f(|_| httpcodes::HTTPOk)))
+        .bind("127.0.0.1:59080").unwrap()
+        .start().unwrap();
+
+#     actix::Arbiter::system().send(actix::msgs::SystemExit(0));
+    let _ = sys.run();
+}
+```
 
 
 ## Multi-threading
@@ -18,7 +46,7 @@ use actix_web::*;
 fn main() {
     HttpServer::<TcpStream, SocketAddr, _, _>::new(
         || Application::new()
-            .resource("/", |r| r.f(|r| httpcodes::HTTPOk)))
+            .resource("/", |r| r.f(|_| httpcodes::HTTPOk)))
         .threads(4); // <- Start 4 threads
 }
 ```