Various PyTorch 0.4.0 updates

[marikgoldstein]

This commit fixes a few deprecation warnings thrown by PyTorch 0.4.0.

Merge of Variable and Tensor:

• change Variable(a_tensor) to a_tensor

Support for PyTorch Scalars of 0-dimension

• changeloss.data[0] to loss.item()

Naming conventions in nn.init

• change nn.init.constant to nn.init.constant_
• change nn.init.uniform to nn.init.uniform_
• change nn.init.xavier_uniform to nn.init.xavier_uniform_

This pull request does not fix TypeError: Object of type 'Tensor' is not JSON serializable thrown by save_checkpoint on line 83 of train.py, which seems to be an issue new to PyTorch 0.4.0.

Thanks! This is a great implementation!!! Mark

[loudinthecloud]

Thanks for the pull request, much appreciated!

The TypeError was due to the cost variable being a Tensor as well, fixed it locally. I'll rebase and merge this branch.

[loudinthecloud]

Merged as 3c64937cb075e737528ff7ecf02b2c1c6d8347a1 Thanks!

[marikgoldstein]

Thanks! Awesome repo.