Django-user-management

* BREAKING: Add a app_name to each of the urls entry points. See the docs/views.md for updated default url namespaces.
* Fix Pillow security issue
* Drop support for Python < 3.6
* Add support for Python 3.6, 3.7 and 3.8
* Drop support for Django < 1.11
* Add Django 2.2 and 3.0 to travis
* Update djangorestframework>=3.9.1 for XSS fix https://github.com/encode/django-rest-framework/commit/75a489150ae24c2f3c794104a8e98fa43e2c9ce9
* Update incuna_mail>=4.1.0 for Django 3 support

* Backwards incompatible: Use `CIEmailField` from Django 1.11 for a case-insensitive email field.

* Fix bug using VERIFIED_QUERYSTRING with a LOGIN_URL.

* Allow VerifyUserEmailView get_redirect_url function to accept an extra string.
* Allow user login after email verification providing a setting is true in an apps settings file.
This works in Django 1.10.

* Fix email verification when `LOGIN_URL` is a url name.

* Update `VerifyUserEmailView` to redirect to login without providing a next.
* Redirect to the login when attempting to verify an email address that is already verified.