Remove Vagrant/Ansible environment

[KlaasH]

This project was originally set up as Docker-in-Vagrant, partly to handle the limitations of running Docker on Macs at the time and partly to support running the analysis on Windows machines. Neither of those requirements exists any more—we don't need Windows support and Mac has actually done a reversal, so Docker-on-host works but Virtualbox doesn't.

The Docker-on-host setup is already partly/mostly working, but the task here is to:

• Remove the resources related to Vagrant/Ansible provisioning
• Make sure the tooling and documentation is all updated to reflect the new Docker-only setup