SCIO: Bundle SCIO in a single image for easy CLI and CI/CD deployment

There are a few ways to look at this:
- multiple images with a docker compose
- single image (pulp style) with only docker
- some wrapper script to make it easier to run a one-of scan and get the results back (dealing with volumes, exports, etc.)

In the end this is to simplify using SCIO in CI or as a CLI.

We have an action at https://github.com/nexB/scancode-action/ but this is complex to integrate this elsewhere as there are a lot of moving parts.