- Do not trigger legaldb

- Set Django version to 1.11
- Update to 3.0, notable changes
* Installed module changed from registration to django_registration
* Python 3.7 support
* Minimum Django version is now 1.11
* Include tests and runner in source distribution
* Make it possible to distinguish different types of activation failures
* Add the ability to detect when the account has already been activated
* Remove RegistrationFormNoFreeEmail
* Clean up the weird ancient handling of
success_url/get_success_url()
* Make the one-step backend a little more robust with custom users
* Correct use of is_secure() in activation email context
* Template directory rename, and renamed activation email body template
and renamed activation failure template
* Made the HttpRequest available to activation email contexts
* Rename URL patterns
* Rename the HMAC backend
* Added a form class doing case-insensitive username uniqueness checks