Trusted certs

[jhu-arod]

Would be great to have the ability to specify a list of trusted certificates so they are bundled upon cluster creation.

[akostadinov]

I think that you can just add these to the system trust store instead of wrapping into the cluster-up tool. That is add certificates to /etc/pki/ca-trust/source/anchors/, then execute `update-ca-trust extract". This is useful for example to make cert of internal container registries trusted. I think you also need to restart docker service though.