Generalize deployment tests

I generalized the deployment tests by removing all of the hard coded node names, ports, and nics, and instead imported them from a JSON file.  The JSON file's name is defined in deployment.cfg, and the file is used to populate information about the environment that the deployment tests will be run in.
Maybe:

    nodes = [{'label': n.label,
              'nic': n.nics[0].label,
              'port': n.nics[0].port.label}
             for n in nodes]

That makes this code shorter, and lets you iterate over nodes below, rather than having to do `n0` and `n1` separately.