* Change to FQCN with ansible-lint fixer
Since ansible-base 2.10 (later ansible-core), FQCN is the new way to go.
Updated .ansible-lint with a production profile and removed fqcn in skip_list.
Updated .yamllint with rules needed.
Ran ansible-lint --fix=all, then manually applied some minor changes.
* Changed octal value in molecule/ipv6/prepare.yml
* Apply "become" on roles instead of plays
This leads to facts being gathered for the "regular" login user, instead
of root.
* Do not rely on ansible_user
Instead of reading ansible_user (which may or may not be defined), this
patch lets the roles rely on Ansible facts [1].
[1]: https://docs.ansible.com/ansible/latest/playbook_guide/playbooks_vars_facts.html
