GMM to take advantage of labels if provided to fit(X, y = None), to be useful for prediction in pipeline

GMM to take advantage of labels if provided, to be useful for final/prediction stage of a pipeline.
Here is the gist:
https://gist.github.com/dashesy/5577051
And here is the issue I created:
https://github.com/scikit-learn/scikit-learn/issues/1957