message: Properly document sequence_length parameter of dynamic_rnn
  Fixes
diff: @@ -580,9 +580,8 @@ def dynamic_rnn(cell,
  tuple of Tensors each with dimensions `[batch_size, ...]`.
  sequence_length: (optional) An int32/int64 vector sized `[batch_size]`. Used
  to copy-through state and zero-out outputs when past a batch element's
  - sequence length. This argument enables this API to extract
  - the last VALID state of RNN instead of a PADDED time step, so it is
  - for correctness.
  + sequence length. This parameter enables users to extract the last valid
  + state and properly padded outputs, so it is provided for correctness.
  initial_state: (optional) An initial state for the RNN. If `cell.state_size`
  is an integer, this must be a `Tensor` of appropriate type and shape
  `[batch_size, cell.state_size]`. If `cell.state_size` is a tuple, this
  