OBS worker instance running in docker container. Obsworker comes with
rather complicated init script, which is hereby replaced with a script,
./start-obsworker that does the most simple case - chroot builds.
.. is done via environment variables (or file), e.g.:
watch out for trailing whitespaces!
if you set OBS_TMPFS=8000, an 8G tmpfs mount will be used for builds
Note, that OBS master must be able to connect to the worker instance on given
OBS_PORT, and the OBS_PORT must match what is given in -p
Starting OBS worker
docker run --privileged -d -h workername --env-file obsworker.env -p 12345:12345 suihkulokki/obsworker