Since https://issues.apache.org/jira/browse/SPARK-9610, we start to support instance weighting in ML.
However, Clustering and other impl in features still do not support instance weighting.
I think we need to start support weighting in KMeans, like what scikit-learn does.
It will contains three parts:
1, move the impl from .mllib to .ml
2, make .mllib.KMeans as a wrapper of .ml.KMeans
3, support instance weighting in the .ml.KMeans