Libmachine logs can be enabled with --v=3 or higher.  --v=7 turns on
debug level info.  This will simplify the debugging control plane and
allow us to transition off of libmachine logs in the future.

updated docs.

This was coming from a dependency somewhere that's now gone. Also update help text.

The k8s update updated cobra as well, so the generated help text changed.

documentation.  Added test in Travis for making sure docs are up-to-date.