modify  predict/predictClass function  (#2868)
modify  predict/predictClass function  (#2868)

* predictClass output modification

* predict/predictClass function modification in Beta Api

* predict/predictClass function modification

* predict/predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

* predictClass function modification

intel-analytics/BigDL,intel-analytics/BigDL,yangw1234/BigDL,intel-analytics/BigDL,yangw1234/BigDL,yangw1234/BigDL,yangw1234/BigDL,intel-analytics/BigDL