Fixed #23132 -- Removed confusing clause in auth docs.
Forwardported 1.6.6 release note for #19107.
Fixed #23107 -- Made runserver output respect --no-color.
Fixed flake8 errors.
Fixed #23134 -- Fixed typos in docs/ref/models/querysets.txt.

Thanks Josh Kupershmidt.
Fixed #23067 -- Updated docs to use django-admin
Fixed test failure on Windows.

os.close(fd) is needed to avoid "The process cannot access the file
because it is being used by another process"
Fixed #23112 -- Field.get_choices tries to index an iterable
Fixed the previous commit for Python3.