Refactor calls to `SaniGetWorker.schedule`

[macool]

Current implementation is via whenever:
0,15,30,45 * * * * /bin/bash -l -c 'cd /home/pi/bandango && bin/rails runner -e production '\''SaniGetWorker.schedule'\'' >> /home/pi/bandango/log/cron.log 2>&1'

New implementation should avoid reloading the environment as it takes too much on the Pi. Maybe add a SaniGetSchedulerController#index so that the crontab wgets it to schedule

[macool]

.. Or use sidetiq