Documentation for "clicks" plugin

As requested in the pull-request #13 here's some documentation for the plugin.

Btw: Can I suggest an easier/more structured approach to API documentation?

Maybe we can discuss this in an issue or I'll simply try to convert as much as possible to something more manageable. 

Plus:  Using the Gruntfile commit ( #12  ) as a base we could extend it to compile the documentation out of something else like Markdown into HTML.