Decided i'm not into this whole magic int j thing
Implement first part of step 1b

Using regex instead of magic j
Factor out r1 regex
Factor out method for regex in r1 matching
Extract duplication of string literal regex, concept of matching word
Extract capturing and replacing

This doesn't feel quite right to me yet. Too much reuse maybe.
Modify stem in place instead of using magic k

I don't really like mixing the idea of moving the k position of the end
of the word around AND replacing things in the original string; it's too
clever. We'll see if I need to put this back for performance later.
Rename b to stem
Bump version. A little step1b, a lot of refactoring