Improve controller login security

[FastGeert]

• When installing the controller nodes from iso:
  • Install & configure teleport in systemd
  • Close the public ip access to the default sshd in the firewall.
• Add documentation for teleport usage
• Create a healthcheck that cleanes up ssh-keys from the system that should not be there
• Add check to meneja to prevent iso download if the certificate present in the configuration is not valid or does not match with the domain
• Add check to meneja to make sure that the gig password is strong enough (8 characters, small, capital & numbers needed), and differs for each environment.

[grimpy]

Done and deployed on staging