Changes

Summary

1. merged
2. tuned signature (again);
3. trim context of persistent data;
4. trim context of persistent data;
5. proper file name;
6. trim context of persistent data; tuned signature;
7. clarified data operations, with trim_context and transfer;
8. tuned;
9. trim context of persistent data; tuned;
10. trim context of persistent data;
11. removed unused material;
12. trim context of persistent data;
13. trim context of persistent data; no need to trim context for del operations;
14. tuned;
15. tuned whitespace;
16. more operations;
17. optional trace of created theory values;
18. more operations;
19. auxiliary operation for space profiling;