Separate the pieces.

I'm not sure if this is the final state yet. I don't really
like how I have to specify the controllers with:

   .Get("route", func(w, r) { controller(w, r) })

...so I'll have to probably wrap this in a closure in the
individual controller function (like a handlerFunc). I also
don't like how to initialize templates yet. More work is
needed in that area!