Outdated docker images

[jonkerj]

I've been running (and loving) NIPAP for a while, and would like to run it containerized. However, the docker images provided from this project are wildly outdated.

It would be great if someone could build up to date docker images, or even better, put it into the CI so it is done automatically. If the devs like help with the latter, I'm glad to PR this into the current CI that builds the debian packages.