Added support for QML to Weasel

Qt 5.3 added a QtWebsockets module which makes Weasel the perfect candidate for a QML/JS Clojurescript repl.

I added a weasel.repl.qml namespace which tries to mirror weasel.repl as much as possible.

I also added a trivial weasel.impls.print ns to so that the same repl server can set the print function regardless of whether it's a regular Websocket, QML or possibly say a Node.js repl.

I posted details here about how I actually got a REPL working in QML: https://groups.google.com/forum/#!topic/clojurescript/bSBfH1hazSg