Some Goonstation improvements(?)

[pali6]

Based on discussion in the OpenDream Discord here the changes from our fork. Accompanied by Crossedfall/crossed-cogs#23

• Support for arbitrary versions.
• Normalization of indentation so you can use e.g. two spaces.
• Cleanup of the output.
• Multiple Docker paths are tried on Linux

Let me know if any of this sucks or you don't want it and I'll remove it from the PR.

[pali6]

I was bypassing Dockerfile because just passing the relevant arguments to run was the first solution I found back when I was doing this a couple of years ago. Now it should be done more correctly (I hope) by building the beestation/byond image and then building the test image from the Dockerfile.