Implementation of Softmax classifier using PBblas library

Classify.Softmax_Sparse : the implementation of SoftMax using ML/Mat

Classify.Softmax : the implementation of SoftMax using PBblas Library

test/explanatory/Softmax : test of classify.softmax on a toy dataset

test/explanatory/SoftMax_CancerDataset :test of classify.softmax on the cancer dataset which has 96 samples of size 20 (20 features)

test/explanatory/SoftMax_MNISTdataset : test of classify.softmax on the MNIST dataset which has 60'000 samples of size 784 (784 features)

test/explanatory/SoftMax_Sparse_MNISTdataset : test of classify.softmax_sparse on the MNIST dataset which has 60'000 samples of size 784 (784 features)