merged branch GromNaN/patch-5 (PR #408)

Commits
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8cf66cbc Improve validator provider doc

Discussion
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Improve validator provider doc

Add a small note and fix rst syntax of this page : http://silex.sensiolabs.org/doc/providers/validator.html#validating-arrays

doc/providers/validator.rst

@@ -70,8 +70,11 @@ method::
         }
     });
 
-Validating Arrays
-~~~~~~~~~~~~~~~~~
+Validating Associative Arrays
+~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+
+Validating associative arrays is like validating simple values, with a
+collection of constraints::
 
     use Symfony\Component\Validator\Constraints as Assert;