Look over install/usage instructions

[gunnarx]

In the README there are several ways to install the tools described, and some are untested or described as deprecated. Decide on the best way (or ways?) and describe them. Preferrably also make automated test to verify the instructions (and/or automate all steps using a script).

Also, is asdf a useful tool to support? https://github.com/asdf-vm/asdf

[gunnarx]

Related but not replacing the above issue:

Work is in progress on a docker setup so there's a guaranteed tested/stable setup of the required python version and packages. That might also be used in CI testing, but the GitHub environments are quite easy to set up. We'll see.

[gunnarx]

Docker containers are now complete so it is a controlled way of executing the tools without dependency problems.

However, I would still prefer to have clear and always guaranteed to work instructions to people who want to invoke the tools it in a different way, using a virtual environment, and perhaps without a virtual environment too.