How do we insert some middleware that pulls query parameters in Funcatron?
Here's an example of a Middleware provider that intercepts the
incoming request and pulls out a parameter. Based on the parameter,
the Map of information about the request is updated.
So... what does the incoming request Map look like? It's
based on the Clojure Ring request, but with String key names rather than
Clojure keyword key names.
One can short-circuit the response by returning
a Map with response keys (as String) and values.