Fix clojure jar dependency
Retrofit the original API in ororo.core

This avoids breaking backwards compatibility. The asynchronous client
functions live in the ororo.async namespace.
Allow to pass in optional opts map to httpkit's get

This makes it possible for the caller to tune parameters like timeouts
and keepalive times.
Upgrade to latest data.json library version
Doc clarification
Update clojure, remove old http library dep
Avoid reflection warning
Add option to pass in a callback

The callback will be called when the request is fulfilled.
Update documentation
ororo 0.2.0