* Remove unused method
* Prefabricate user in category_user_spec.rb
* FIX: Remove notification_level from category_users unique indexes
* FIX: CategoryUser#batch_set wasn't updating pre-existing records
* Improve tests for CategoryUser#batch_set
* FIX: changed was being reported incorrectly
* DEV: Rewrote query to do a bulk insert
* DEV: remove unnecessary parentheses