See merge request !1501

Closes #275

See merge request !1492

Closes #276

See merge request !1507

See merge request !1490

See merge request !1502

See merge request !1500

See merge request !1496

Closes #270

See merge request !1495

See merge request !1494

Without `NamedRange_::operator==`, in the comparison between two
`NamedRange_` instances `nr1` and `nr2` C++20 would not be able to
choose between `(Range_&)nr1 == nr2` and `(Range_&)nr2 == nr1`.

Remove the property type added as a comment to the Conf.py files. It was
entirely cosmetic and often wrong (e.g. maps were annotated as `# list`).

Relates to issue #219.

- replace `.format` with f-strings
- replace `setattr` with direct `_properties` access in `merge`

More precisely, json data come from the JSONSink and this produces a list of non ordered items, one may call it a set.
Unfortunately JSON does not have such a concept so an ordered list is produced and the validator was naturally checking that the order was correct

See merge request !1483