new rule: Never pass -ip to h2o when running multi-machine. Any failure in ip determination by h2o is considered a h2o bug (h2o
 on hadoop relies on h2o self-determination.
Also created h2o_sandbox.py which breaks out the check_sandbox_for_errors.py function, so it can be run standlone to 'grep' the h2o stdout/stderr files in sandbox after an Runit style test is run.
Merge branch 'master' of github.com:0xdata/h2o