Dynamic LSTM

The DynamicLSTM in MACE is implemented for Kaldi's time delay RNN models.

The following pictures explain how to fuse components into a DynamicLSTMCell.

Before fusing:

../_images/FuseLSTM.png

After fusing:

../_images/DynamicLSTM.png

For more details about LSTMNonlinear in Kaldi, please refer to [LstmNonlinearityComponent](http://kaldi-asr.org/doc/nnet-combined-component_8h_source.html#l00255)