Summary
- tuned whitespace;
- prefer static object, while class is required for "services" (see 47eb96592aa2);
- clarified directories; clarified names;
- tuned signature;
- tuned: prefer explicit update operation for immutable options;
- tuned message;
- more robust type, with explicit default;
- tuned usage message;
- clarified signature;
- more robust defaults;
- merged
- added lemmas relpow_trans[trans] and relpowp_trans[trans]
- more on disjunctive addition/subtraction