* FarmEvents now schedule all events up front
* Executions are stored in the database
* Regimens now schedule all items up front
* Executions are stored in the database
* fix Deleting a FarmEvent with a running RegimenInstance
* `execute`int and `schedule`ing a CeleryScript are not separate things
* Everywhere `scheduling` and `executing` CeleryScript updated to use
the new API