Experimenter does not print line when a job ends

[nils-wisiol]

When there are no new jobs in the queue, experimenter won't output a status line whenever a job as ended. So the last line always looks like:

Sat Jan 26 02:39:28 2019 90 jobs total, 69 finished, 21 running, 0 queued, progress 0.77, remaining time: 3:12:00

There will be no update when there are 20, 19, ... jobs running.

[nils-wisiol]

Fixed via #127