Incorporate Morphy

[oxinabox]

It might be nice to incorporate mophy to perform stemming.
NLTK does: www.nltk.org/howto/wordnet.html#morphy
wordnet's online interface also does.

[chengchingwen]

Is it sensible to mimic the implementation in NLTK ?

https://github.com/nltk/nltk/blob/f6d17eb02f89439474cd50dad2142b20aa40dae9/nltk/corpus/reader/wordnet.py#L1717-L1815