Add Snowball (Porter2) Stemmer as an option

[bnvk]

You currently offer the widely used Porter Stemmer and also the Lancaster Stemmer. The former is less aggressive and the later is often times too aggressive. It would be nice to implement the Lancaster as well which is in the middle with aggressiveness as well as performance

Also, awesome library. Thanks for making. I'm incorporating it into a user friendly GUI app at the moment :)

[namirsab]

Its actually pretty easy to do, you just need to use the apply method of the Corpus and pass the stemmer function, or if you don't want to mutate the exiting corpus, just call the map method.

[namirsab]

@Planeshifter are you planning to release the latest version ( the one with the code in the master branch).
It includes some changes that are useful, like the apply function.

[Planeshifter]

Need to finish a few things and didn't find the time yet. Will try to get it landed soon. Thanks for your interest!

[namirsab]

@Planeshifter thank you for such a nice library!