[MLLIB] [spark-2352] Implementation of an 1-hidden layer Artificial Neural Network (ANN)

The code contains a multi-layer ANN implementation, with variable number of inputs, outputs and hidden nodes. It takes as input an RDD vector pairs, corresponding to the training set with inputs and outputs.

Next to two automated tests, an example program is also included, which also contains a graphical representation.
@manishamde: In most cases, one hidden layer is enough. For some special functions two hidden layers are needed. This is a nice text about the choice of number of layers and number of nodes per layer:
http://www.heatonresearch.com/node/707
Especially the number of nodes per layer depends heavily on the particular problem.