Updating a job or trigger should update the nextFireTime trigger property

Jobs and triggers have a property to enable/disable them called hipposched:enabled (boolean). Triggers have properties that determine when the trigger must run. The hipposched:nextFireTime property of a trigger is the property that is queried when the scheduler periodically searches for new triggers to fire and it should be updated when the trigger timing changes, it must be added when the job and trigger become enabled and it should be removed when the job or trigger become disabled.