PY3: used six.moves.cStringIO to fix StringIO import in text_k_means.py
Merge branch 'py3' of https://github.com/raulgarreta/scikit-learn into py3
Merge branch 'py3' of https://github.com/sdegryze/scikit-learn into py3
PY3: update the documentation on testing.mock_mldata_urlopen
PY3: ensuring file stream is read as binary