Thanks Tim Graham for the review.

Thanks LaMont Jones for the report and patch.

Follow up to 8db889ea.

admin_views.Recommendation.recommender: (models.E006) The field 'recommender'
clashes with the field 'recommender' from model 'admin_views.title'.

Reflects behavior changes in PEP 495 (Local Time Disambiguation).

Fixed #26830 -- Prevented the 'with' templatetag from resetting the cycle variable to its initial state.

Refs #26830 -- Added a test for a named cycle template tag inside an ifchanged block and a for loop.

Fixed #27041 -- Documented that built-in middleware are compatible with MIDDLEWARE and MIDDLEWARE_CLASSES.

The spec refers to it as a 'directive' rather than a 'tag':
https://tools.ietf.org/html/rfc6797#section-6.1.2

After https://hg.python.org/cpython/rev/4ea79767ff75/,
test_strips_underscore_headers fails with:
'Stub' object has no attribute 'sendall'.

As makemessages uses several settings for proper run (FILE_CHARSET,
LOCALE_PATHS, MEDIA_ROOT, and STATIC_ROOT), we should require settings
configuration for this command.

Thanks Tim for the review.