geotrellis/geotrellis — pull request #661 by lossyrob (2013-12-02 19:19:47+00:00)
Title: Seperated out mutable histogram conecpt, made ConstantHistogram

This is some refactors that I did as part of trying to solve #626. I took out the changes that I decided were not worth implementing as explained in that issue, but this is a valid refactor.