Removed the hdf5 backend and tests with batch normalization

bob/learn/tensorflow/analyzers/SoftmaxAnalizer.py

bob/learn/tensorflow/datashuffler/Base.py

bob/learn/tensorflow/initialization/Initialization.py

bob/learn/tensorflow/initialization/Xavier.py

bob/learn/tensorflow/layers/Conv2D.py

bob/learn/tensorflow/layers/Layer.py

bob/learn/tensorflow/network/Chopra.py

bob/learn/tensorflow/network/SequenceNetwork.py

bob/learn/tensorflow/script/train_mnist.py

bob/learn/tensorflow/script/train_siamese_casia_webface.py

bob/learn/tensorflow/test/test_cnn.py

bob/learn/tensorflow/test/test_cnn_pretrained_model.py

bob/learn/tensorflow/test/test_cnn_scratch.py

bob/learn/tensorflow/test/test_dnn.py

bob/learn/tensorflow/trainers/Trainer.py

bob/learn/tensorflow/util.py