pruning and missing values features added in CART
Merge pull request #2255 from mazumdarparijat/CART

prune method added and missing values handled
cross validation pruning added + changes in clone_tree method in TreeMachine
class structure for CHAID added
chi2_cdf and fdistribution_cdf added
Implemented the basis for convolutional neural nets
Merge pull request #2259 from yorkerlin/variational-likelihoods

the variational base class using numerical intregation
Merge pull request #2264 from mazumdarparijat/CHAID2

class structure for CHAID added
Merge pull request #2265 from mazumdarparijat/CHAID1

chi2_cdf and fdistribution_cdf added
CMultilabelSOLabels class modified along with unit tests to remove memory leaks
CMultilabelModel class added with unit tests
Merge pull request #2270 from abinashpanda/multilabel_model

SOMultilabel model for multilabel classification
added support for non-linearties to CConvolutionalFeatureMap
CMultilabelAccuracy class created along with modifications of CStructuredAccuracy and CMultilabelSOLabels for multi-label classification accuracy
Implemented max pooling for CConvolutionalFeatureMap
so_multilabel.cpp example added for multilabel classification
added support for arbitrary strides during convolution
CART cv_prune test added, TreeMachine clone_tree refactored
Merge pull request #2266 from khalednasr/convnets

Implemented the basis for convolutional neural nets
coverity scan defects fixed