Adds initial support for Rabbitmq in Ansible using the CONFIG_EXTERNAL methods.
Additionally, this refactors some of the Rabbitmq config script to allow for
reuse by CONFIG_EXTERNAL.
Partially Implements: blueprint ansible-service
Change-Id: I1765548f7e4f1258eb8a49e2a23242955f52655d
Add set_configs function that implements the flow from the proposed
ansible-multi spec. Move start.sh to config-internal.sh to preserve existing
behaviour.
config-externall.sh copies the appropriate configs in from the bind'd
location and sets permissions and ownership appropriately.
Partially Implements: blueprint ansible-multi
Change-Id: I53fca0660451087f273fefc3c63e0d8cf1a2c096