Improve `KeyedVector.wmdistance` (#2326)
Improve `KeyedVector.wmdistance` (#2326)

* Improve wmdistance

* reformat

RaRe-Technologies/gensim,gojomo/gensim,piskvorky/gensim,gojomo/gensim,gojomo/gensim,piskvorky/gensim,piskvorky/gensim,RaRe-Technologies/gensim,gojomo/gensim,RaRe-Technologies/gensim,RaRe-Technologies/gensim