Issue #1903784 by linclark, damiankloip, effulgentsia: Move serialization to own module.

core/lib/Drupal/Core/CoreBundle.php

core/modules/jsonld/jsonld.info

core/modules/rest/rest.info

...lization/lib/Drupal/serialization/Encoder/JsonEncoder.php

...alization/lib/Drupal/serialization/Encoder/XmlEncoder.php

...Drupal/serialization/Normalizer/ComplexDataNormalizer.php

...on/lib/Drupal/serialization/Normalizer/ListNormalizer.php

...on/lib/Drupal/serialization/Normalizer/NormalizerBase.php

...b/Drupal/serialization/Normalizer/TypedDataNormalizer.php

...erialization/RegisterSerializationClassesCompilerPass.php

...lization/lib/Drupal/serialization/SerializationBundle.php

...ib/Drupal/serialization/Tests/EntitySerializationTest.php

...tion/lib/Drupal/serialization/Tests/SerializationTest.php

core/modules/serialization/serialization.info

core/modules/serialization/serialization.module

...lib/Drupal/serialization_test/SerializationTestBundle.php

...ib/Drupal/serialization_test/SerializationTestEncoder.php

...Drupal/serialization_test/SerializationTestNormalizer.php

...lization/tests/serialization_test/serialization_test.info

...zation/tests/serialization_test/serialization_test.module