Add meta/requirements.yml; support ansible-core 2.11

[nhosoi]

The vpn role requires ansible.netcommon.ipaddr. Add a requirement for the ansible.netcommon collection.

Updated .ansible-lint to support meta/requirements.yml.

Updated meta data in main.yml.

[nhosoi]

Thank you, @richm. Could you please merge this pr as I don't have the permission?

[richm]

@nhosoi whoops - forgot to add change the README.md like this: https://github.com/linux-system-roles/storage#requirements

[nhosoi]

@nhosoi whoops - forgot to add change the README.md like this: https://github.com/linux-system-roles/storage#requirements

Please review: https://github.com/linux-system-roles/vpn/pull/35 Thanks!