Add ssl support for keystone token generation

When kubernetes-master:keystone-credentials is related to openstack-integrator:credentials, a kube-keystone.sh is generated. That is used to grab a keystone token. Right now the curl in that script does not support ssl (passing in a cert).

It seems like we want to check if OS_CACERT is set (in the novarc) and if so, pass it to the curl.

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I can add support for it manually by:

* Changing the curl in the kube-keystone.sh file to something like this:
token=$(curl --cacert /home/ubuntu/root.pem -s -i -H "Content-Type: application/json" -d "${data}" "${OS_AUTH_URL}/auth/tokens" |grep 'X-Subject-Token')

* scp root.pem to kubernetes-master host

* export the openstack variables

* then run the script

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(I'm not sure if this bug falls under kubernetes-master or openstack-integrator so feel free to move)