Use the test-matrix role from devstack-gate to define a base set of
services to be enabled for the controller and compute nodes.
Extend the local conf module to handle the base set of services.
Since the test-matrix defines services for primary and subnode nodes, we
need a multinode job to test that this works. Add a new host group
called subnode that includes the non-controller hosts. Add a new job
that runs devstack on a two nodes environment.
Using service from the test matrix enables swift in the gate, so we need
to set SWIFT_HASH for devstack to work.
Depends-on: Ie36ba0cd7cfcd450b75000a76a64d856f2a83eba
Depends-on: Id9ad3be4be25e699f77d6b5a252f046ce8234f45
Change-Id: I379abf482c89122533324e64fefbff3d5a618a89
7d4446541d