* Attempt to slowly build inner data format used by Pure and Mixed Games,
* Added some Null objects to Model::NullFactory.
* Several more "drafts" added to GameFactory/PlainData model.
* Added custom exception declarations.
* Test changed for better readability.
* Extracted Data interface,
* More sketch-code for PlainData.
* Majority of PlainData sketch.
* Changed some ones into more readible (replaced (*object).method with object->method),
* Added missing isNotNull = false into some null objects.