docs: parse_expression, add links to parse_type module and Cardinalit…

…yField support.

Add support for Gherkin v6 grammar (Rule and Example, ... aliases).

This should simplify to use Example Mapping concepts in feature files.

* Use Cucumber "gherkin-languages.json" to support Gherkin v6 keyword
  aliases and simplify spoken language support in the future.

upload: Only one format is allowed now, disable ZIP format.

VERSION: 1.2.5

Merge test_importer.py fix into into mcepl-unicode_crash_251

BUMP-VERSION: 1.2.4 (was: 1.2.4a1)

BUMP-VERSION: 1.2.3 (was: 1.2.3a20) and release it.

FIX: Include behave4cmd0 in sdist bundle.

Finalize version: 1.2.3a19

FIX: Update version 1.2.2.18 in setup.py