Final round of help notes improvements

Author: javiereguiluz

src/AppBundle/Events.php

@@ -12,14 +12,17 @@
 namespace AppBundle;
 
 /**
- * Contains all events thrown in the Symfony demo application.
+ * This class defines the names of all the events dispatched in
+ * the Symfony Demo application. It's not mandatory to create a
+ * class like this, but it's considered a good practice.
  *
  * @author Oleg Voronkovich <oleg-voronkovich@yandex.ru>
  */
 final class Events
 {
     /**
-     * See http://symfony.com/doc/current/components/event_dispatcher.html#naming-conventions.
+     * For the event naming conventions, see:
+     * http://symfony.com/doc/current/components/event_dispatcher.html#naming-conventions.
      *
      * @Event("Symfony\Component\EventDispatcher\GenericEvent")
      *