* Replace ugettext_lazy with gettext_lazy for Django 4.x support
* Remove Signal providing_args for Django 4.x support
* Replace url with re_path for Django 4.x support

* Add tox tests for Django 3.0, 3.1, 3.2, 4.0, 4.1
* Add new Python versions for Travis tests
* Bump Travis Ubuntu version for Python 3.10
* Bump Postgres (9.2 -> 11) for Django 4.0 to work
* Fix Travis config warnings

* Note Postgres version for Django 4.0 in README
* Update CHANGELOG
* Update Python versions badge in README

Co-authored-by: Vladimir Logunov <logunov@mybook.ru>

• Commit f28f6ef
• Compare 1.4.0
• Tag 1.4.0

v26