Sepia Mode / Theme Support

[benjamindovinh]

First off, I'm really excited to be a part of this.

I'd like to request a feature for "Sepia Mode" or "Theme" Support. Anything that would benefit different contrast and color needs.

:)

[jefftangx]

Actually love Sepia mode on Instapaper. Would probably wanna rename standardize/name all our CSS classes and then do #563