Binary Restricted Boltzmann Machines using k-step Contrastive Divergence.

Run: ./run.sh

Refs:
   Fischer, Asja, and Christian Igel. "Training restricted Boltzmann machines: an introduction." Pattern Recognition 47.1 (2014): 25-39.
   Hinton, Geoffrey. "A practical guide to training restricted Boltzmann machines." Momentum 9.1 (2010): 926.
   Chang, Chih-Chung, and Chih-Jen Lin. "LIBSVM: A library for support vector machines." ACM Transactions on Intelligent Systems and Technology (TIST) 2.3 (2011): 27.
   http://deeplearning.net/tutorial/rbm.html
   20 news data set http://qwone.com/~jason/20Newsgroups/