minor #1368 Documentation code-block fixes (bobalazek)

This PR was merged into the 1.3 branch.

Discussion
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Documentation code-block fixes

Commits
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0f401b77 Documentation code-block fixes

README.rst

@@ -2,9 +2,7 @@ Silex, a simple Web Framework
 =============================
 
 Silex is a PHP micro-framework to develop websites based on `Symfony
-components`_:
-
-.. code-block:: php
+components`_::
 
     <?php
 

doc/providers/http_cache.rst

@@ -58,9 +58,7 @@ setting Response HTTP cache headers::
     in `Trusting Proxies
     <http://symfony.com/doc/current/components/http_foundation/trusting_proxies.html>`_.
 
-    If you would be running Varnish in front of your application on the same machine:
-    
-    .. code-block:: php
+    If you would be running Varnish in front of your application on the same machine::
 
         use Symfony\Component\HttpFoundation\Request;
         
@@ -69,9 +67,7 @@ setting Response HTTP cache headers::
 
 This provider allows you to use the Symfony reverse proxy natively with
 Silex applications by using the ``http_cache`` service. The Symfony reverse proxy
-acts much like any other proxy would, so you will want to whitelist it:
-
-.. code-block:: php
+acts much like any other proxy would, so you will want to whitelist it::
 
     use Symfony\Component\HttpFoundation\Request;
         

doc/providers/serializer.rst

@@ -45,9 +45,7 @@ Registering
 Usage
 -----
 
-The ``SerializerServiceProvider`` provider provides a ``serializer`` service:
-
-.. code-block:: php
+The ``SerializerServiceProvider`` provider provides a ``serializer`` service::
 
     use Silex\Application;
     use Silex\Provider\SerializerServiceProvider;
@@ -73,4 +71,3 @@ The ``SerializerServiceProvider`` provider provides a ``serializer`` service:
         ));
     })->assert("_format", "xml|json")
       ->assert("id", "\d+");
-