Fixed a few typo

README.md

@@ -134,19 +134,19 @@ Creating a class that inherits `WebSocketService` class.
 
 For example, if you want to provide the echo service,
 
-    ```cs
-    using System;
-    using WebSocketSharp;
-    using WebSocketSharp.Server;
+```cs
+using System;
+using WebSocketSharp;
+using WebSocketSharp.Server;
 
-    public class Echo : WebSocketService
-    {
+public class Echo : WebSocketService
+{
   protected override void onMessage(object sender, MessageEventArgs e)
   {
     Send(e.Data);
   }
-    }
-    ```
+}
+```
 
 For example, if you want to provide the chat service,