Try using spaCy text classifier

We could try using the text classifier available in spaCy instead of gradient boosting and see how it behaves.

@marco-c What's the priority of this issue? Is it worth trying out the spacy model at this stage?

Yes, definitely. It would require a bit of juggling around with the code, but it'd be useful to try.

where do we want to use a spacy classifier? nlp.py? spacy vectorizer is being used in a few files.