All tests PASS for SerializableJson. Serialization API changes

* Serializable has gained a protected properties property
  to be used by derived classes to save on demand lists of
  serializable properties
* Serializable provides both abstract and virtual methods. Virtual
  methods have a default implementation to be used by implementators
  allowing to override on derived classes of implementators
* Serializable implementators must implement abstract methods but if
  they want to derived classes to override them, they must be declared
  as virtual
* SerializableJson has been ported to Serializable. Implements most
  mothods and reuse most of them with default implementation and
  declared as virtual in order to allow to be overriden on derived
  classes.
* All Unit Tests for SerializableJson has been ported to Serializable
  and new SerializableJson and finish with PASS state.
* SerializableObjectModel has been ported to Serializable. No tests
  yet.