Performance improvements? about colorschemes.jl

[rafaqz]

No problem, it might be a while until I get this done anyway

[cormullion]

Hi there! Yes, anything you can do to improve this package would be very welcome! Performance hasn’t been a priority till now - I’m mostly concerned with the interface, and this code isn’t a bottleneck for me. Thanks!

travis.yaml also needs updating ... I was going to do it soon...

[rafaqz]

Great! I'm trying to get colorschemes 40 million times a second on a laptop, so it's definitely a bottleneck...

I'll have a look at travis as well.

[cormullion]

I ended up fixed the travis.yaml file, so as to generate the latest documentation... I've just been adding colorscheme data, not changing the code. I'll probably make a new release soon, but without any code changes (no performance improvements, sorry...!).