Adds Vagabond integration testing and setup

* Adds instructions for using Vagabond to test the
Chef repository.
* Add a new testing environment file that is specific
to Vagabond
* An ops, compute controller and compute worker node
added to the vagabond environment

Change-Id: Id15201b9b870c51d337d8d07fca5e42ca8aaf385
Merge "Adds Vagabond integration testing and setup"