change sigmoid and tanh to torch from nn.functional

[dhpollack]

I received the following message when running python check.py

miniconda3/lib/python3.6/site-packages/torch/nn/functional.py:1006: UserWarning: nn.functional.sigmoid is deprecated. Use torch.sigmoid instead.
  warnings.warn("nn.functional.sigmoid is deprecated. Use torch.sigmoid instead.")
miniconda3/lib/python3.6/site-packages/torch/nn/functional.py:995: UserWarning: nn.functional.tanh is deprecated. Use torch.tanh instead.
  warnings.warn("nn.functional.tanh is deprecated. Use torch.tanh instead.")
Forward: Baseline (Python) vs. C++ ... Ok

afterwards I get

Forward: Baseline (Python) vs. C++ ... Ok

[goldsborough]

Thanks!