* [made user blankable](https://github.com/pinax/pinax-referrals/issues/38)
3.0.2
* Use Django 2.0 import for `reverse`
3.0.1
* Change `is_authenticated` to property in models.py
3.0.0
* Add Django 2.0 support * Drop Django 1.8, 1.9, 1.10 and Python 3.3 support * Convert CI and coverage to CircleCi and CodeCov * Add URL namespacing * Update installation requirements for django>=1.11 * Add PyPi-compatible long description * Standardize documentation layout * Remove unused doc build support