Implement agent of processing subtypes

[KovalM]

This agent should:

1. be initiated after finish of knowledge build;
2. find all sc-construction with explicit subtype indication.
   For example:
   
3. Indicate subtype on sc-core level:
   
4. Remove access edge from subtype node:
   
   Note: should be implemented in separate branch.
   Depends on: Implement ScAgent's test framework #307 Remove setting sc-element subtype logic from scs loader #385