Quick and dirty adaptation of kmpp from apache commons. Very sub
optimal. Will replace with actual dependency hierarchy when I get around
to it.
Being annoyed by the lack of a central place for distance functions, I
have made a package called moa.distance. Ideally this is where things
should reside, but perhaps I will follow suit with everyone else and
just keep my nik-naks in the respective algorithm package.
Added a constructor that takes a single instance as the centre.