Previously the FORMAT_MODULE_PATH setting only accepted one string (dotted
module path). A feature has been added to also allow a list of strings.

This is useful when using several reusable third party apps that define new
formats. We can now use them all and we can even override some of the formats
by providing a project-wide format module.

Thanks Anssi Kääriäinen and Tim Graham for the reviews. Refs #17001 and #22650.

Regression from f51c1f59 when using select_related then prefetch_related
on the reverse side of an O2O:

Author.objects.select_related('bio').prefetch_related('bio__books')

Thanks Aymeric Augustin for the report and tests. Refs #17001.

#22667 replaced occurrences of master/slave terminology with leader/follower

When using ManifestStaticFilesStorage, deleted static files would be
correctly cleaned up by "collectstatic --clear", but the manifest file
would still contain the stale entries.

Thanks to tedtieken for the report

This reverts commit a4737bf6.

Fixed #22424 -- MySQL doesn't accept migrations' one-off default values ...

Fixed #22661 -- Move makemigrations tests to the proper class

This reverts commit 5a2556af.

The paragraph was a copy of strictly_above.

Thanks alexdlaird for the report.

This reverts commit 950b6de1.

Considering that these apps only translate their app name, it's not
worth having a whole bunch of po files just for that. The translatable
app name for those apps will be integrated in Django core catalog.

Previously the FORMAT_MODULE_PATH setting only accepted one string (dotted
module path).

This is useful when using several reusable third party apps that define new
formats. We can now use them all and we can even override some of the formats
by providing a project-wide format module.

Used the official terminology listed in
http://docs.oracle.com/cd/B19306_01/network.102/b14212/glossary.htm#i997309

Thanks michael.cherkasov for the report.

makemessages should now automatically distribute translatable
strings in the proper locale files, for Django too
(see 50a8ab7c).

Fixed #22635 -- Make "It worked!" page localizable

Dutch ('nl-NL' and 'nl-BE') has several valid input formats;
see http://nl.wikipedia.org/wiki/Datum_(dagtekening).

Thanks Erik Romijn for review.

Thanks syphar for the review and suggestions.

The `wordwrap` tests were in the `test_wordcount()` method for some
reason. This moves them to their own method, and make consistent use of
double quotes where needed.

This fixes a failing test after applying an optimization of the
utils.text.wrap function by user SmileyChris.