Ability to georegion code based on a string

This enables directly georegion coding against a column containing zip code strings (eg. "98122") instead of having to geocode the zip code to an additional point column and then georegion coding that column against the region polygon.
s/codahale/dropwizard maybe... I am confused by things inside io.dropwizard.metrics having a namespace of com.codahale.metrics.