kubernetes cloud-init script fails when keystone is running on HTTP/2

[Yiu-Chung Lee]

In drivers/common/templates/kubernetes/fragments/make-cert.sh, there is a line

USER_TOKEN=`curl -k -s -i -X POST -H "$content_type" -d "$auth_json" $url \
    | grep X-Subject-Token | awk '{print $2}' | tr -d '[[:space:]]'`

The problem is when keystone is running on HTTP/2, all headers are returned as lowercase, which grep would fail. It should be changed to grep -i X-Subject-Token.

Same applies on drivers/common/templates/kubernetes/fragments/make-cert-client.sh, drivers/common/templates/swarm/fragments/make-cert.py, drivers/k8s_coreos_v1/templates/fragments/make-cert.yaml and drivers/k8s_coreos_v1/templates/fragments/make-cert-client.yaml.

Ref: https://tools.ietf.org/html/rfc7540
8.1.2. HTTP Header Fields
However, header field names MUST be converted to lowercase prior to their encoding in HTTP/2.