LSTM and GRU in JAVA

Reference:

• Fig ref：https://github.com/dophist/kaldi-lstm
• A Note on BPTT for LSTM LM: http://www.slideshare.net/tmasada/a-note-on-bptt-for-lstm-lm
• Colah’s blog: http://colah.github.io/posts/2015-08-Understanding-LSTMs/

**For Peephole lstm, one of h_t-1 and c_t-1 is enough for the gate condition. Using both of them will hurt the performance.(2018-11-16)