Improvement in reference manual examples test automation

[amattioc]

Today the examples in the reference manual are structured in a way that facilitates their use as test cases (csv, json, vtl file types).

Anyway, the json files are not completely aligned with the schema described in the Technical Notes: in fact the actual json files of the examples are just a subsection of the complete json schema. This choice, though improving the readibility of the dataset structure, can create ambiguities to engine developers that want to use the examples as a test suite.

We have to find a way to derive the single json structures from complete json schemes so that the first files can be used in the packaging of the documentation and the second files can be used for test automation.