class Rufus::Scheduler

'cron' jobs get executed if necessary then 'at' jobs.
determine if there are jobs to trigger else to get back to sleep.
(by default 4 times per second). It's meant to quickly
This is the method called each time the scheduler wakes up

def step
  step_unschedule
    # unschedules any job in the unschedule queue before
    # they have a chance to get triggered.
  step_trigger
    # triggers eligible jobs
  step_schedule
    # schedule new jobs
  # done.
end