Use virtualenv for installation of OpenStack projects and
dependencies to avoid conflicts with Python libraries installed
by non-OpenStack binary packages.
Change-Id: I21ecd673b2e93335b1d3dd4e279e940c9d694c3c
Implements: blueprint virtualenv
This brings Kolla images inline with FHS and should make finding
locations of things more consistent and reliable with the linux world
at large.
Change-Id: Iece5b4da4bace0fb8b1f41a65ab2c852ec73e6f8
Closes-Bug: #1485742