Convert TripleO Tasks to Ansible Roles

Ansible tasks are currently embedded in heat templates. This adds complexity to development of new ansible tasks, and makes this work non-reusable by other projects. These tasks should be moved to service-specific ansible roles and imported by the heat templates for use by config-download. Shared resources, such as playbooks and modules, should be created in a new TripleO Ansible project repo "tripleo-ansible".

Roles/playbooks should be able to be used standalone or via Director/config-download.

Development of new roles, tasks, or playbooks would be done as in this example using backup tasks:
openstack/ansible-role-openstack-operations:
tasks/backup_databases.yml
vars/main.yml
    - variable definitions for backup_databases task
defaults/main.yml
    - default vars for backup_databases task

openstack/tripleo-ansible:
backup.yml (playbook that uses include_role: ansible-role-openstack-operations and tasks_from: backup_databases.yml)