Add fail2ban

[cityofships]

• Set up sshd to verbose logging
• Install & configure fail2ban

[cityofships]

This could be baked into the dedicated Bastion image instead of growing TF configuration.

[axelsimon]

What i'd like to do, i think, is just use Fedora CoreOS for this. Minimal OS, running nothing but the SSH server, easy to rebuild (directly using a ignition file, or using Terraform). Adding Fail2ban as part of that would make complete sense.