title: Keras implementation of LSTMCell (The class uses optional peep-hole connections, optional cell clipping, and an optional projection layer).
body: <p>According to my understanding, Keras LSTM cell is similar to Tensorflow</p>
  
  <p><strong>BasicLSTMCell(RNNCell)</strong>.
  However, I am looking for the implementation of Tensorflow</p>
  
  <p><strong>LSTMCell(RNNCell)</strong>
  in Keras (LSTMCell : The class uses optional peep-hole connections, optional cell clipping, and
  an optional projection layer). <a href="https://github.com/tensorflow/tensorflow/blob/master/tensorflow/python/ops/rnn_cell_impl.py" rel="noreferrer">https://github.com/tensorflow/tensorflow/blob/master/tensorflow/python/ops/rnn_cell_impl.py</a>
  <a href="https://research.google.com/pubs/archive/43905.pdf" rel="noreferrer">https://research.google.com/pubs/archive/43905.pdf</a>
  Hasim Sak, Andrew Senior, and Francoise Beaufays.
  "Long short-term memory recurrent neural network architectures for
  large scale acoustic modeling." INTERSPEECH, 2014.</p>
  
  <p>I am wondering without writing a custom layer, is there is any way to use this Tensorflow LSTMCell in Keras or is it already available?</p>