Django-extensions

-----

Changes:

- Improvement: shell_plus, not save ipython history when using Jupyter
- Improvement: docs, fix spelling mistakes
- Improvement: tests, move to Github Actions instead of Travis
- Improvement: drop_test_database, delete all cloned test databases (1637)
- Improvement: setup.py, Added minimum Django>=2.2 version to PyPI package
- Improvement: shell_plus, fix --command globals / locals error

-----------

Changes:

- Improvement: setup.py, Added minimum Django>=2.2 version to PyPI package

-----

Changes:

- Improvement: graph_models, add option --app-labels
- Improvement: shell_plus, update shell_plus for jupyterlab 3
- Improvement: tests, add Python 3.9

-----

Changes:

- Improvement: pipchecker, sleep 60s if pypi raises a fault
- Improvement: add django_zero_downtime_migrations to list of supported postgresql engines
- Improvement: use list of supported database engines from settings for all database commands
- Improvement: reset_db, documentation
- Fix: tests, Python 3.9 fixes for some tests
- Fix: runserver_plus, parsing of RUNSERVER_PLUS_EXTRA_FILES

-----

Changes:

- Improvement: runserver_plus, survive syntax and configuration errors part II
- Improvement: tests, refactor test runner
- Improvement: sqlcreate, support postgresql unix domain socket

-----

Changes:

- Improvement: setup.cfg, remove universal flag from wheel, we only support Python 3 and up
- Improvement: sqlcreate, fixed mentioned of old syncdb
- Fix: runserver_plus, stop catching SyntaxError since reload for it was not working properly