Hey @kushalkolar et al,

great package! i was just looking around the image utils here and noticed that you require matplotlib to generate colormaps but, understandably, don't include matplotlib in your dependencies.

when working on napari and other related image libs, I also wanted to use colormaps without having to depend on matplotlib, and made cmap, a lib that only depends on numpy and provides all the matplotlib colormaps (and many more) and basic mapping functionality. the lib exports to many third-party colormap objects. Would you be interested in looking at a PR that uses cmap here?