use pygments token that look neat in light terminal profiles as well

current set of pygments token used by [lexer](https://github.com/cloudnativelabs/kube-shell/blob/master/kubeshell/lexer.py) looks pretty in dark terminal profiles like solarized dark, molokai etc. but does look dull in light colored profiles.

figure a set of tokens or a way that look neat on both light and dark terminal profiles.