Extends the Serializer collection with our custom serializer/deserializer
functions for the UserDefinedFieldsDefinition entity.
When serializing returns a json string that contains all fields of the user defined fields definition.
When de-serializing, user defined fields definition fields are extracted
and a com.atomizesoftware.spin.models.UserDefinedFieldsDefinition is returned.
Extends the Serializer collection with our custom serializer/deserializer functions for the UserDefinedFieldsDefinition entity. When serializing returns a json string that contains all fields of the user defined fields definition. When de-serializing, user defined fields definition fields are extracted and a com.atomizesoftware.spin.models.UserDefinedFieldsDefinition is returned.