[INT-1487] [INT-1913] CUPS image futureproofing

[zachariaserlandsson]

As part of the printerlion tech-debt cleanup I decided to do a little facelift of this Docker image as well, seeing as it was quite outdated (based on Ubuntu 16 base image).

• Added canary version of CUPS image so it could be used when testing.
• Updated CUPS Dockerfile
  • Removed locale tinkering with locales apt-get package, shouldn't be needed anymore (UTF8 included in base Ubuntu image nowadays).
  • Moved installation of all dependencies into Dockerfile, instead of having it both there and in the separate install.sh script.
  • Not using tini anymore - instead using init: true parameter when spinning up CUPS container from printerlion. Accomplishes the same thing - running process as PID 1, so that signal forwarding and reaping of zombie processes is done.
  • Updated the build script in the driver tarball, so that it no longer uses sudo (run as root anyway, so not needed).

[SimonOsnes]

Amazing!

Would this make it so cups can run on macs as well or is that problem not connected to this at all?

[zachariaserlandsson]

Amazing!

Would this make it so cups can run on macs as well or is that problem not connected to this at all?

To be perfectly honest, wasn't event aware of this issue at all :') So it wouldn't necessarily fix it I'd say..