Fixed #18176 -- Added test for year lookups with year < 1000

Thanks Tomas Ehrlich for the initial test
Fixed #19854 -- Turn Django's own Selenium tests off by default.
Fixed #19801 - Added brackets to input_formats.

Thanks leandron85@ for the suggestion.
Merge pull request #847 from fhahn/ticket_18176

Fixed #18176 -- Added test for year lookups with year < 1000
Use built-in fixture support rather than calling loaddata in setUp().
Fixed #18144 -- Restored compatibility with SHA1 hashes with empty salt.

Thanks dahool for the report and initial version of the patch.
Updated the release process docs to reflect the current practices.

Fixed #17919.
Fixed #6195 -- Documented caching options for javascript_catalog.
Fixed #19634 -- Added proper __hash__ methods.

Classes overriding __eq__ need a __hash__ such that equal objects have
the same hash.

Thanks akaariai for the report and regebro for the patch.
Fixed #18191 -- Don't consider Accept-Language redundantly in cache key.

Thanks to choongmin for the original patch.
Fixed a caching test on Python 3.
Updated an inaccurate comment.

Tests can run nearly as fast under PostgreSQL and MySQL as under SQLite
with a bit of configuration and the speedup is always a good thing.
Moved test_templates to templates to prevent issues with regressiontests/templates later on.
Removed __init__.py files.
Merged regressiontests and modeltests into the test root.
Adjusted runtests to the new layout.
Adjusted coveragerc
Renamed some tests and removed references to modeltests/regressiontests.
Renamed a template to be found by the loaders.
Updated docs to reflect new tests layout.

Thanks to Ramiro Morales for the initial patch.