[SPARK-1225, 1241] [MLLIB] Add AreaUnderCurve and BinaryClassificationMetrics

This PR implements a generic version of `AreaUnderCurve` using the `RDD.sliding` implementation from https://github.com/apache/spark/pull/136 . It also contains refactoring of https://github.com/apache/spark/pull/160 for binary classification evaluation.