Statusbar and sidebar improvements

[mhkeller]

I've made some changes on my fork to fill in values were going to the defaults and thus didn't look too spacegray-y. Here's what I've added: mhkeller@c285eae

It generally removes the default blue color from the statusBar and selection. Makes the git colors and makes the git and warning colors more consistent. I have other things that I'm going to do on my fork that will diverge a bit, but if you want these improvements I'm happy to make a PR.

[mihai-vlc]

hi @mhkeller ,

A PR would be welcomed.
Please also include a screenshot of an example code.