Merge remote-tracking branch 'upstream/master'

Conflicts:

deeplearning4j-core/src/main/java/org/deeplearning4j/nn/BaseNeuralNetwor
k.java

deeplearning4j-core/src/main/java/org/deeplearning4j/util/MatrixUtil.jav
a

deeplearning4j-examples/src/main/java/org/deeplearning4j/example/lfw/LFW
RBMExample.java