This is an extended version of the WordNetLemmaViewGenerator. If the word is
a verb, then it first looks up the lemma dictionary. If found, it returns the
lemma. Otherwise, it checks against a known list of contractions. Finally, it
goes to WordNet. If the word is present in WordNet, the lemma from WordNet is
used. Otherwise, it defaults to the word itself (with case).
This lemmatizer lowercases words before finding their lemma. This could lead
to errors. This requires the file resources/verb-lemDict.txt in the
classpath, which can be obtained from cogcomp-common-resources.