Fixes for running under django 1.6

Minor changes:

- django.contrib.auth.views.password_reset* now uses base64 encoding for the uid.
- DeleteView changed got get_success_url() works and now expects self.object to be populated.  Almost never matters, except that VacationDeleteView overrides default delete() behavior and wasn't populating self.object.
- Removed an unused view, as everything auth-related should be going through django-registration.