minor #7493 [Serializer] Add new default normalizers (dunglas)

This PR was submitted for the 3.1 branch but it was squashed and merged into the 3.3 branch instead (closes #7493).

Discussion
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[Serializer] Add new default normalizers

Refactoring of the serializer doc to list new normalizers introduced in 3.1 and enabled by default.

Commits
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f1a5290 [Serializer] Add new default normalizers

Author: javiereguiluz

serializer.rst

@@ -85,21 +85,37 @@ you need it or it can be used in a controller::
 Adding Normalizers and Encoders
 -------------------------------
 
-Once enabled, the ``serializer`` service will be available in the container
-and will be loaded with four :ref:`encoders <component-serializer-encoders>`
-(:class:`Symfony\\Component\\Serializer\\Encoder\\JsonEncoder`,
-:class:`Symfony\\Component\\Serializer\\Encoder\\XmlEncoder`,
-:class:`Symfony\\Component\\Serializer\\Encoder\\YamlEncoder`, and
-:class:`Symfony\\Component\\Serializer\\Encoder\\CsvEncoder`) and the
-:ref:`ObjectNormalizer normalizer <component-serializer-normalizers>`.
-
-You can load normalizers and/or encoders by tagging them as
+Once enabled, the ``serializer`` service will be available in the container.
+It comes with a set of useful :ref:`encoders <component-serializer-encoders>`
+and :ref:`normalizers <component-serializer-normalizers>`.
+
+Encoders supporting the following formats are enabled:
+
+* JSON: :class:`Symfony\\Component\\Serializer\\Encoder\\JsonEncoder`
+* XML: :class:`Symfony\\Component\\Serializer\\Encoder\\XmlEncoder`
+
+As well as the following normalizers:
+
+* :class:`Symfony\\Component\\Serializer\\Normalizer\\ObjectNormalizer` to
+  handle typical data objects
+* :class:`Symfony\\Component\\Serializer\\Normalizer\\DateTimeNormalizer` for
+  objects implementing the :class:`DateTimeInterface` interface
+* :class:`Symfony\\Component\\Serializer\\Normalizer\\DataUriNormalizer` to
+  transform :class:`SplFileInfo` objects in `Data URIs`_
+* :class:`Symfony\\Component\\Serializer\\Normalizer\\JsonSerializableNormalizer`
+  to deal with objects implementing the :class:`JsonSerializable` interface
+* :class:`Symfony\\Component\\Serializer\\Normalizer\\ArrayDenormalizer` to
+  denormalize arrays of objects using a format like `MyObject[]` (note the `[]` suffix)
+
+Custom normalizers and/or encoders can also be loaded by tagging them as
 :ref:`serializer.normalizer <reference-dic-tags-serializer-normalizer>` and
 :ref:`serializer.encoder <reference-dic-tags-serializer-encoder>`. It's also
 possible to set the priority of the tag in order to decide the matching order.
 
 Here is an example on how to load the
-:class:`Symfony\\Component\\Serializer\\Normalizer\\GetSetMethodNormalizer`:
+:class:`Symfony\\Component\\Serializer\\Normalizer\\GetSetMethodNormalizer`, a
+faster alternative to the `ObjectNormalizer` when data objects always use
+getters and setters:
 
 .. configuration-block::
 
@@ -310,3 +326,4 @@ take a look at how this bundle works.
 .. _`ApiPlatform`: https://github.com/api-platform/core
 .. _`JSON-LD`: http://json-ld.org
 .. _`Hydra Core Vocabulary`: http://hydra-cg.com
+.. _`Data URIs`: https://developer.mozilla.org/en-US/docs/Web/HTTP/Basics_of_HTTP/Data_URIs