Show error if data_path does not exist or is None (see #1102)
Show error if data_path does not exist or is None (see #1102)

spacy-io/spaCy,explosion/spaCy,aikramer2/spaCy,honnibal/spaCy,honnibal/spaCy,explosion/spaCy,aikramer2/spaCy,explosion/spaCy,recognai/spaCy,explosion/spaCy,aikramer2/spaCy,recognai/spaCy,recognai/spaCy,spacy-io/spaCy,honnibal/spaCy,aikramer2/spaCy,explosion/spaCy,aikramer2/spaCy,recognai/spaCy,spacy-io/spaCy,recognai/spaCy,honnibal/spaCy,explosion/spaCy,spacy-io/spaCy,spacy-io/spaCy,aikramer2/spaCy,recognai/spaCy,spacy-io/spaCy