Enable deployment from macOS by adding to vars.tf

[redhatgov]

Enable deployment from macOS by adding to vars.tf

[c0dyhi11]

@liveaverage why not move the artifacts download and deployment into the nginx box?
This will make our lives easier and we can control the the install ENV.
Basically just update all local-exec to remote-exec.

If you think this is a good Idea. I can take on this work.

[liveaverage]

@wtcross and I debated this, too. For testing it made sense to use local-exec so I didn't add provisioning time (when re-downloading binaries for oc and openshift-install) each time I tore down and reprovisioned a new cluster. Since I think moving to remote-exec will resolve this issue and allow us to stage bare metal images to speed-up deployment, I think I'll knock this out today.

[liveaverage]

Fixed by #38. This should technically work fine on Windows too, but only if we remove the step to copy/scp the generated kubeconfig: https://github.com/RedHatSI/openshift-packet-deploy/blob/master/terraform/output.tf#L6