Fixed #22223 -- Prevented over-escaping URLs in reverse()

And follow more closely the class of characters defined in the
RFC 3986.
Thanks Erik van Zijst for the report and the initial patch, and
Tim Graham for the review.
Fixed #22351 -- Removed usage of lambdas in model field options.

Thanks claudep for review.
Fixed #13794 -- Fixed to_field usage in BaseInlineFormSet.

Thanks sebastien at clarisys.fr for the report and gautier
for the patch.
Revert "Improve cookie based session backend docs." refs #20418

This reverts commit d9c01da1f8ba3d4e0947fd1d619c8f4a9b013360.

This is poor advice as it breaks the test client login (refs #22934).
We can add a note like this back after refs #22986 is resolved.
Fixed #19671 -- Added warnings that null and validators are ignored for ManyToManyField.

Thanks Loic Bistuer and Tim Graham for help and review.