[MRG] Linear Neural Networks/Softmax Regression (#555)
[MRG] Linear Neural Networks/Softmax Regression (#555)

* Linear Neural Networks/Softmax Regression

* Linear Neural Networks/Softmax Regression

* Linear Neural Networks/Softmax Regression

* Linear Neural Networks/Softmax Regression

* Linear Neural Networks/Softmax Regression

* Linear Neural Networks/Softmax Regression
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