Add a theme for people using solarized colors scheme

Solarized is a colorscheme for terminals and applications alike.
 
Users of solarised in htop cannot see the "(Black,Black)" in any theme.
This is an attempt to provides those users a way to see all information provided by the default htop theme.

This is a screenshot of my proposed theme and the default one.
![screenshot](https://cloud.githubusercontent.com/assets/43065/4909744/a8e103f2-6476-11e4-8cb4-f836b5fdc178.png)

To achieve this currently, users need to get htop source, modify and recompile htop. 
Alas recompiling (htop) is not a possibility in some environments.

I acknowlege that solarized is not the first nor the last colorscheme available and one might not want to clutter htop with many schemes.
Being able to build a custom color scheme at runtime from htop itself or a .htop would probably be a more elegant way to solve the issue.
Unfortunatly I don't have the technical know-how to provide such a contribution.

Credit:
I used alexeiz's gist for inspiration https://gist.github.com/alexeiz/4657334.