Add more colors

[jdiaz97]

I think it would be cool to have these palettes: https://www.thinkingondata.com/something-about-viridis-library/
I can do a PR, but I'd like to know if this package is still mantianed

[psiphi75]

Yes, create the PR and I'll review and merge it, then publish the package to crates.io.
Those colour palettes look cool.