Submit improvements upstream

[rtgibbons]

Any thoughts, or previous effort, to get these change submitted to upstream? It would directly fix ansible/ansible#18579

https://github.com/ansible/ansible/blob/devel/contrib/inventory/proxmox.py

[xezpeleta]

I didn't even try it, as this is not a custom fix, it's an alternative version which collects different fixes and improvements.

In fact, it includes code from PRs (like PR #17247) not merged by Ansible.