add setup-sh script for installing dependencies and setting python3

[vtjnash]

Add a quick simple bash script for installing the python3 dependencies that are needed to run the main script, assuming already that virtualenv is installed with python3.

[aleclearmind]

Mmmh, I think we want to package this as a proper Python package and publish it on pypi, more than going this route.

[vtjnash]

I don't think those are necessarily mutually exclusive

[Artoria2e5]

Bit specific on the versions, aren't we?

[vtjnash]

No, that would be typical for a pip file. Though nowadays we'd use uv instead of this or pypi or whatever