Begin the normalizers doc

Author: GuilhemN

components/serializer/encoders.rst

@@ -4,8 +4,8 @@
 Encoders
 ========
 
-Encoders basically turn **arrays** into specific **formats** and vice versa.
-They implement :class:`Symfony\\Component\\Serializer\\Encoder\\EncoderInterface` for encoding (arrays to specific formats) and :class:`Symfony\\Component\\Serializer\\Encoder\\DecoderInterface` for decoding (specific formats to arrays).
+Encoders basically turn **arrays** into **formats** and vice versa.
+They implement :class:`Symfony\\Component\\Serializer\\Encoder\\EncoderInterface` for encoding (array to format) and :class:`Symfony\\Component\\Serializer\\Encoder\\DecoderInterface` for decoding (format to array).
 
 You can add new encoders to a Serializer instance by using its second constructor argument::
 

components/serializer/normalizers.rst

@@ -3,3 +3,21 @@
 
 Normalizers
 ===========
+
+Normalizers turn **objects** into **arrays** and vice-versa.
+They implement :class:`Symfony\\Component\\Serializer\\Normalizer\\NormalizerInterface` for normalizing (object to array) and :class:`Symfony\\Component\\Serializer\\Normalizer\\DenormalizerInterface` for denormalizing (array to object).
+
+You can add new normalizers to a Serializer instance by using its first constructor argument::
+
+    use Symfony\Component\Serializer\Serializer;
+    use Symfony\Component\Serializer\Normalizer\ArrayDenormalizer;
+    use Symfony\Component\Serializer\Normalizer\GetSetMethodNormalizer;
+
+    $normalizers = array(new ArrayDenormalizer(), new GetSetMethodNormalizer());
+    $serializer = new Serializer($normalizers);
+
+Built-in encoders
+-----------------
+
+The Serializer Component provides several normalizers for most use cases:
+    *