This object can be constructed by passing it
a mapping of stack name to TripleoInventory
objects.
It has a merge method which merges all of the
TripleoInventory objects into one OrderedDict
which appends the stack name and an underscore
to each host group to avoid name collisions.
It has a write_static_inventory method which
writes the merged OrderedDict into an Ansible
inventory.
Change-Id: I522f1acbd39ad36ae1fec896188d3e20e0575566
Implements: blueprint split-control-plane-unified-inventory
aeaa571765