v0.4.0

This release adds support for using color libraries to organize color gradients. New functions are clibrary, clibraries, cgradients and default_cgrad. The release puts the cmocean gradients in their own library, and adds Bokeh's colorcet library, as well as the colorbrewer color library.

v0.3.0: Merge pull request #6 from KristofferC/kc/adaptive-grid

add function to compute an adapted grid of a function on an interval