Porter Stemming Algorithm 2.1

This is a fairly faithful implementation of the Porter stemming algorithm that reduces English words to their stems.

There is a deviation in the way compound words are stemmed, such as hyphenated words and words starting with certain prefixes. For instance, "international" should be reduced to "internation" and not "intern," but an unmodified version of the alorithm will do just that. Currently, only hyphenated words are accounted for.