Better document configuration option

On the [custom badges page](https://shields.io/badges) or somewhere easily reachable, there should be examples for the options. Especially for *style* [flat, flat-square, plastic, for-the-badge, social] I'd like to directly see the options without having to try them. The example also shows that named colors are supported and uses *blue*. I'd like to see what the other named colors are. The color produced by a *blue* badge is not the same color as using the CSS color name *blue*, so it would be interesting to see.

Of course it would also be interesting to have examples of icons etc., but the above things are more relevant I think.