Update the installation - provide a Docker image

[robogeek]

I started to go through the Guide for this project. The Installation section says to use TorqueBox, whatever that is seems to be something for running Ruby code? I have no idea, since I've never used Ruby. But - the TorqueBox website is down #11

The issue related to that issue ends with a note describing that because that website is down, we cannot retrieve TorqueBox. The only route is to use a new version of Ruby to somehow get all the dependencies, then use an old version of Ruby to run TorqueBox.

In other words - running the VTN under TorqueBox is no longer possible. Therefore, the VTN should be updated so it is runnable using modern software rather than ancient (and probably crufty) versions of Ruby, and not using this TorqueBox thing which is obviously a dead unsupported project.

There's another issue - #12 - talking about an inability to compile part of this using the OpenJDK. The OpenJDK build recommended in the manual is pretty old, and the code and build procedures should be updated to modern stuff.

And, while you're at it, bundling everything as a Docker image, with a Docker Compose file to manage setting up the VTN and Database and Apache - all that would fabulously update this project so it is runnable in the 2020's.