Add the ability to set the prometheus.scrape component to use https

[petewall]

On OpenShift, kube-state-metrics and Node Exporter already exist, but they only respond on https. We'll need to be able to use https, set the bearer token, and disable tls verification:

  scheme     = "https"
  bearer_token_file = "/var/run/secrets/kubernetes.io/serviceaccount/token"
  tls_config {
    insecure_skip_verify = true
  }