Update HBMP code for pytorch 0.4.1

This is a PyTorch 0.4.1 compatible fork of https://github.com/Helsinki-NLP/HBMP

Install dependencies

The following dependencies are required (versions used in brackets):

• Python (3.6.7)
• Pytorch (0.4.1)
• Numpy (1.15.4)
• Torchtext (for preprocessing) (0.3.1)
• SpaCy (for tokenization) (2.0.18)

For SpaCy you need to download the English model

python -m spacy download en