Dataset CLI

Not sure how to get rid of the warning though in a simple way:

/usr/lib/python3.6/runpy.py:125: RuntimeWarning: 'd3m.container.dataset' found in sys.modules after import of package 'd3m.container', but prior to execution of 'd3m.container.dataset'; this may result in unpredictable behaviour
  warn(RuntimeWarning(msg))

There is also the following warning which I do not get locally but it is seen on CI:

/usr/local/lib/python3.6/dist-packages/d3m/namespace.py:4: UserWarning: Module d3m was already imported from /usr/local/lib/python3.6/dist-packages/d3m/__init__.py, but /builds/datadrivendiscovery/d3m is being added to sys.path
  import pkg_resources