Settings schema without prefill

[iLLiCiTiT]

Changes

• loading of settings schema is handled using SchemaHub
• schemas are not resolved before are passed to root entity
  • schemas must be resolved in entities that can possibly have 'schema' or 'template' type as children
• json files that can't be parsed won't cause error if are not used
• this is required step as now filling of entity children had to be handled in single function which had to know all entities structure but with this change it is entity based so entity and it's schema data can have different definitions of children data (required for this issue)

How to test

It's tricky as everything should work almost the same way.

[kalisp]

It seems not to break anything :)