Install Ironic software from git.

Required options can be provided via heat.
For example:

  ironic:
    db: mysql://ironic:unset@192.0.2.2/ironic
    service-password: unset
  keystone:
    host: 192.0.2.2
  glance:
    host: 192.0.2.2
  rabbit:
    host: 192.0.2.2
    password: guest

