Dockerize

[thattommyhall]

Should fix #351, work-around for #350 if they use Docker instead, addresses how to agree versions from #343

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[gammazero]

In order for this to run correctly on most users' systems, a few small changes are needed.

[gammazero]

LGTM

[gammazero]

@thattommyhall Added a couple of other suggestions post-review.