[ticket/1430] Fix use and namespace order in docs

WEBSITE-1430

Author: danieltj27

development/extensions/tutorial_controllers.rst

@@ -44,10 +44,10 @@ Every controller should contain at least two methods:
 
     <?php
 
-    use \Symfony\Component\HttpFoundation\Response;
-
     namespace acme\demo\controller;
 
+    use \Symfony\Component\HttpFoundation\Response;
+
     class main
     {
         /* @var \phpbb\config\config */