Enabled makemessages to support several translation directories

Thanks Rémy Hubscher, Ramiro Morales, Unai Zalakain and
Tim Graham for the reviews.
Also fixes #16084.
Closed file after reading pot file

Faulty line was introduced in 50a8ab7cd1.
Fixed comment typos.
Documented the house style for gender neutral pronouns.
Removed gender-based pronouns per [c0a2daad78].
Fixed #21358 -- Allowed runserver on non-English locales

Thanks svartalf for the report.
Refs #21230 -- removed direct settings manipulation from template tests
Fixed #21535 -- Fixed password hash iteration upgrade.

Thanks jared_mess for the report.
Fixed incorrect type for max_length.
Fixed #21543 -- Removed base_dir attribute in StaticFilesHandler.

This code seems to be an artifact of AdminMediaHandler removed in [5c53e30607].
Fixed #21545 -- autoreload kqueue events weren't cleared which caused an infinite loop.
Merge pull request #2016 from loic/ticket21545

Fixed #21545 -- autoreload kqueue events weren't cleared which caused an infinite loop.
Fixed #21538 -- Added numpy to test/requirements/base.txt

Thanks Tim Graham for the report
Fixed #13476 -- Added support for color in console output under Windows.

Detect and use the services of the ANSICON third-party tool if it's
available.
Fixed #21546 -- Strengthened kqueue detection.

Thanks Loic Bistuer.
Fixed 21406 -- Made blocktrans 'trimmed' option preserve line numbers.

Thanks Bouke Haarsma for report, fix and initial patch.
Added link to localized formatting doc from main index.
Migrate prompts if you need makemigrations, runserver prompts for migrate
Add --dry-run option to makemigrations
Add clone() method to Field to get clean copies of it.