fix for -uc/--usecloud to match Cloud.json result. This works now
  python test_simple.py -uc

for connecting to existing cloud (like if you first did  java -jar ../../build/h2o.jar)
(-uc defaults to localhost:54321 if no argument given

So this should work for Ray and his ide, without having to use the 'python test_simple.py -ccj h2o-nodes.json'  method from h2o1

Not clear yet how you would pass a --usecloud parameter with nose. Maybe a separate config file with fixed name that's discovered in the local directory. nose doesn't easily support parameter passing on the command line.
Maybe radu has some config file idea  (that's separate from our legacy config files that were mostly about cloud building)