Fixes all the notification request specs that were xited. This should help us feel more comfortable making changes to notifications.
Also made a small (performance?) improvement by using an already defined variable.
* Move follow and reaction aggregation into Notification model to avoid re-compute
* Ugh. Fixing schema
* Update tests
* Skip some tests in notifications_spec
* Remove stream and add new notification views
* Actually remove Stream
* Move followers query to async method
* Remove unused tests and fix query
* Try using without delay instead
* Add without delay and escape HTML
* Make all tests pending for now
