Fixed #23288: deconstruct() ignoring related_name
Complemented 1.6 release notes for 457c16d0d6

And accessorily added missing bits fixing #23293.
Forward port of 2cbafd814 from stable/1.7.x
Fixed typo in docs/howto/custom-model-fields.txt.
Fixed #23162 -- Renamed forms.Field._has_changed() to has_changed().
Fixed #23269 -- Deprecated django.utils.remove_tags() and removetags filter.

Also the unused, undocumented django.utils.html.strip_entities() function.
Fixed #23287 -- Updated error message for classonlymethod decorator.
Fixed typo in tests/migrations/test_operations.py
Fixed #18355 -- Added ordering options to list based generic views.

Added MultipleObjectMixin.ordering and get_ordering().

Refs #21450.
Fixed #23278 -- Documented django.db.backends.schema logger
Fixed #23294 -- Add related_name to existing migrations.

Thanks to Florian Apolloner for the review; refs #23288.
Fixed #23296 -- Fixed RunPython code sample in Migration Operations.
Fixed #23295 -- Removed unnecessary fix_location_header request.get_host() check.
Fixed syntax highlighting and indentation in docs/topics/logging.txt.
Merge pull request #3072 from collinanderson/23295

Fixed #23295 -- Removed unnecessary fix_location_header request.get_host() check