Changes

Summary

1. tuned;
2. merged
3. provide tmp_dir for server session;
4. clarified signature: flexible base_dir;
5. clarified exported messages, e.g. suppress "information", "tracing"; export "legacy_feature" as "warning", in accordance to console default output;
6. clarified signature: prefer selective include_sessions;
7. clarified signature: more uniform session_id;
8. clarified signature;
9. clarified signature: do not expose somewhat accidental internal options;
10. misc tuning and clarification;
11. more documentation;
12. clarified result;
13. tuned;
14. clarified error result, without JSON object from "session_build"; clarified regular result;
15. proper order of matches: Server.Error is an instance of Exn.ERROR;
16. clarified result;
17. clarified markup according to common Command.Results;
18. make baliL and baliR symmetric
19. proof of concept for algebraically founded bit lists
20. tuned proof
21. prefer convention to place operation name before type name