Add TripleO template overrides file
Add TripleO template overrides file

This patch adds a template_overrides file which can be
used to build Kolla packages that work with TripleO.
The intent is to use this for tripleo-ci, and as
a default for upcoming python-tripleoclient features
to build kolla images for TripleO.

This can also be consumed by downstreams like RDO to build
TripleO containers.

Change-Id: I4d6875990e3d40c537fec1c9493261d3086c1db1

openstack/tripleo-common,openstack/tripleo-common