* Finished the functions.

* Started doing the test function.

* Added the batch_normalization operation to the numpy backend.

* forgot an argument

Change line 82 so the reg exp works as it says on token above in the comment
because else it gives - AttributeError: 'NoneType' object has no attribute 'strip'

* #13266 Update lstm_seq2seq.py(from 22% to 87% acc)

I added the codes for applying one-hot encoding on the end of sentences about encoder_input_data, decoder_input_data, and decoder_target_data. I added an accuracy metric for model training. The original code has 22% accuracy, but the proposed code had 87% validation accuracy.

* Update lstm_seq2seq.py

I update code according to PEP8.

* Update lstm_seq2seq.py

Remove whitespace according to PEP 8.

is_tensor_or_variable(x) is undefined and replaced by
K.is_tensor(x) or K.is_variable(x).

Fixes #13306.

# Conflicts:
#	keras/backend/tensorflow_backend.py

* Add SpecificityAtSensitivity metric.

* Fixing some lint issues.

* Fixing some lint issues.

* Adding AUC, SensitivityAtSpecificity metrics.

* Fixed failing test.

* Adding FalsePositive metric class.

* Adding TruePositives, TrueNegatives, FalseNegatives metric classes.

Add metrics CosineSimilarity, MeanAbsoluteError, MeanAbsolutePercentageError, MeanSquaredError, MeanSquaredLogarithmicError, RootMeanSquaredError.

* Adding LogCosh, Poisson, KLDivergence metrics.

* Adding crossentropy  metrics.