Support unevaluatedProperties in draft (version) 2019-09

[kamok]

Is your enhancement related to a problem? Please describe.

The problem is the age old issue where ref to other schemas and using additonalProperties:false doesn't allow json schema to detect the additional ref(s) and bans them from being used.

Here's a SO posts on this: https://stackoverflow.com/questions/22689900/json-schema-allof-with-additionalproperties

Describe the solution you would like

The solution was already released in the draft (version) 2019-09 spec with unevaluatedProperties. Here's some docs on it: json-schema-org/json-schema-spec#556

Describe alternatives you have considered

The alternative right now is ugly, one of the devs that helps contribute to the standard told me about it: https://stackoverflow.com/a/58798563/6174577

It makes large schemas cumbersome and ugly.

[mitodrummer]

+1