(NOT READY)73270866 implement syntax highlight

-  remove `./css` from `.gitignore`
- add third party `css` file from [twitter bootstrap website](http://getbootstrap.com/)
@marexandre 

This is to import [this css file](http://getbootstrap.com/assets/css/docs.min.css) in easier way.

I tried `bower install http://getbootstrap.com/assets/css/docs.min.css --save`, but `bower` rename `docs.min.css` to `index.css` automatically.

https://github.com/bower/bower/issues/561

I did not fiind the way to prevent this. So I did another way.:disappointed_relieved: