Script to migrate Nova BM data to Ironic

This adds the ironic-nova-bm-migrate script which can be used to migrate
node and interface data as well as associated configuration from a
nova-baremetal environment to Ironic.  It requires access to both databases
as well as the Nova configuration file.

Change-Id: I231730ad3e2cb289512c1f1166d4cef3358939f8
Co-authored-by: Adam Gandelman <adamg@ubuntu.com>
Merge "Script to migrate Nova BM data to Ironic"