Add support for multiple playbooks
Add support for multiple playbooks

Update the ceph-ansible workbook so that the $.ceph_ansible_playbook
parameter may also be a list of playbooks. This change is done without
breaking backwards compatability so that if the parameter is passed as
a string which represents a single playbook, then only that playbook is
executed.

Change-Id: I70786ab7b81f9985ddf1148b14ef803c327752b9

openstack/tripleo-common,openstack/tripleo-common