Custom CAs for install source

[Wesley Render]

We would like to be able to fully install Ubuntu over https. Using our own certificate authority to secure the apt repo over https. So for example in our Autoinstall user-data file we would have something like:

apt:
    primary:
        - arches: [default]
          uri: https://repo.internal/
          ca-cert: |
             Our CA certificate goes here...

Talking to dbungert in the IRC they mentioned it is not supported yet, but to create a ticket as it might be something that could be added.