I think sparate 'can not' is better.
Reimplement normalize_tokens, use a tmp array to make it more clear, by the way, make a strict array in rules.
fix casesensitive bug to pass ci, think about 'cannot' or 'can not'?
Merge branch 'master' of https://github.com/liwenzhu/natural into liwenzhu-master
changed the spec to expect 'can not' instead of 'cannot'
Merge branch 'master' of https://github.com/NaturalNode/natural
Remove duplicate variable declaration.
just add some semicolon.
Duplicate unit test.
Merge pull request #139 from liwenzhu/master

Remove duplicate variable declaration.
Use var to delare a variable.
Ok, add var makes benchmars not work, recover benchmarks index.
add french stop words
begin french porter stemmer dev
french p. stemmer prelude small bug fix
link to porter stemmer spec and renames
implements #96, right/left padding for ngrams
updated readme
keysWithPrefix function is very useful for build a full-text indexing or build a search engine.
add tests for keysWithPrefix function.