Changes

Summary

1. Merged
2. More material on totient function
3. merged
4. clarified universal view: include pull_date;
5. clarified signature: PostgreSQL manages high-volume data, SQLite only sees small snapshots;
6. clarified database layout: pull date progression follows Isabelle only, and AFP is derived from that;
7. redundant;
8. Automated merge with bundle:/var/folders/9z/l1x9y3bd16x9_70pdp4703jr0000gp/T/SourceTreeTemp.jiRMht
9. A few more new lemmas
10. more permissive, e.g. for system operations as in 678e00851cfb;
11. tuned;
12. tuned;
13. prefer standard getOrElse;
14. tuned;
15. tuned;
16. more operations;
17. merged
18. clarified directory layout;
19. eliminated unused afp_pull_date table; tuned;
20. slightly more compact file;
21. produce build_log_snapshot, based on small prefix into pull_date history;
22. omit parentheses for the sake of SQLite;
23. more snapshot content;
24. more robust;
25. more direct insert_permissive statement, which avoids somewhat fragile nested transactions;
26. tuned signature;
27. simplified: standard toString is SQL.ident;
28. tuned;
29. tuned signature;
30. clarified signature;
31. tuned signature;
32. tuned signature;
33. tuned signature;
34. clarified modules;
35. clarified pull_date tables; support for SQLite snapshot;
36. views for full PostgreSQL database;
37. eliminated redundant type SQL.View; eliminated unused DROP operations;
38. tuned;
39. tuned signature;
40. tuned;