Because of how Ansible local relative search paths work, the global
"files" and "templates" directories need to be next to the playbooks.
However its not intuitive to look into the playbooks directory to find
the files and templates for a host.
Therefore flatten the playbooks directory to get rid of this confusing
structure.
Also see:
https://docs.ansible.com/ansible/latest/playbook_guide/playbook_pathing.html#resolving-local-relative-paths
Do this to not have dependencies on an NGINX setup.
With those dependencies in place setting up the certificates initially
would be quite painful, since a half-configured NGINX would need to be
there for the challenge and then only after the certificates are
present, the full NGINX configuration could be deployed successfully.