Enable keystone authentication in Ironic

Currently Ironic installation script leaves authenticaiton
strategy in its default value which is noauth. This is not
relevant for the most of development and testing environments.

This patch sets authentication strategy for Ironic to keystone
and specifies the path to the policy file.

Closes-bug: #1233612
Change-Id: Idacbda05663e7ef949cbce0dbdf28eaa36b6a1a9
add lib/stackforge to let us test wsme / pecan from git

wsme and pecan libraries have migrated to stackforge for
development. If we support them in devstack, we can use their git
version instead of the release version, which ensures that they
won't break the rest of OpenStack when they cut a new release.

This is similar to how oslo testing works. Long term we probably
want a more generic mechanism to handle this, but for now, this
should get us rolling, and get them gating.

Change-Id: Icf3475f433081c7c625864107d7e118e214396e1
Start nova-compute with child cell conf

A recent commit broke the cells support and switched nova-compute to always
start with the API cell .conf.  This corrects the regression.

Change-Id: I633344c8784c154f61e751cd0a408196e61525b3
Closes-bug: 1243961
create an UNDO_REQUIREMENTS variable

in the gate, we actually need to *not* roll back the requirements,
otherwise tempest can wedge the world because it runs under tox.

Make a variable that we can set to false in the gate to ensure that
we don't roll back the requirements changes.

Change-Id: I2b842ecc3f6e8b917dd721729640000bd7e7fb78
Merge "Start nova-compute with child cell conf"
Merge "create an UNDO_REQUIREMENTS variable"
Merge "Enable keystone authentication in Ironic"
Merge "add lib/stackforge to let us test wsme / pecan from git"
put the stackforge library installation behind a conditional

we don't actually want to drag in stackforge libraries all the
time, instead ensure that we have enabled stackforge_libs before
doing it.

Change-Id: Ic1c2e3d19e106a2aa0db9725d16a8b207546c23d