[DRE-maint] Bug#853161: All workers run as one systemd unit

[Sjoerd Simons]

Package: obs-worker
Version: 2.7.1-9
Severity: normal

obs-worker is a, well, not very nice init script which runs all the worker
instances (under screen of all things). This means that all systemd's
functionality applies to all instances together rather then specific ones, e.g.
this means resource that one instance cna cause other to hit resource control
limits, restarting can't work per instance etc.

obs-worker should really either be a generator or a simple template systemd
service.

-- System Information:
Debian Release: 9.0
  APT prefers unstable-debug
  APT policy: (500, 'unstable-debug'), (500, 'unstable'), (500, 'testing'), (500, 'stable'), (1, 'experimental')
Architecture: amd64 (x86_64)
Foreign Architectures: i386, armhf

Kernel: Linux 4.9.0-1-amd64 (SMP w/4 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /usr/bin/dash
Init: systemd (via /run/systemd/system)