Fixed typos on the controller.rst

Fixed typos and restructured the Final Thoughts section of controller.rst.

Author: mervinmcdougall

controller.rst

@@ -606,17 +606,16 @@ The ``file()`` helper provides some arguments to configure its behavior::
 Final Thoughts
 --------------
 
-In Symfony, a controller is usualll a class method which is used to accept requests,
-and return a ``Response`` object. Symfony provides an  ``AbstractController`` which
-can be used to extend the controller class, and alllows access to some frequently used utilties 
+In Symfony, a controller is usually a class method which is used to accept requests,
+and return a ``Response`` object. When mapped with a url, a controller a controller's response
+can be viewed.
+
+To facilitate the development of controllers, Symfony provides an  ``AbstractController``.  It
+can be used to extend the controller class allowing access to some frequently used utilities 
 such as ``render`` and ``redirectToRoute``. The ``AbstractController`` also 
 provides the ``createNotFoundException`` utility which is used to return a page
 not found response.
 
-Services are accesible in controllers by typehinting them in the arguments of the controller methods.
-Consequently, objects such as the ``Session`` and ``Request`` objects are injected
-into the controller in this manner.
-
 In other articles, you'll learn how to use specific services from inside your controller
 that will help you persist and fetch objects from a database, process form submissions,
 handle caching and more.