Added ClojureScript support.

Hi James,

I added support for ClojureScript to clout, and because of the
test dependency also to ring-mock.
 
I'm using the ClojureScript version of Clout to match on HTML5
history navigation events, and think this could be useful to
others as well.

All the Clojure test cases are passing and are run via cemerick's
new clojurescript.test library.

Would you be interested to merge this into master and make a
release?

Roman.