Add WebKit reporter

![WebKit Reporter][0]

The initial idea was to create a more convinient reporter for *node-webkit*, you can read about it [here][1]

What I wanted was a nicely formatted _spec_ reporter inside the devtools console. Example [here][2] (open up your console). Currently it's tested only in Chrome, but I guess it should work in Safari too. Firefox is scheduled the support for the extended [console log api][3] for [version 31][4]

In *node-webkit* I'm using mocha programatically, and I'm showing the devtools on startup, example [here][5]


  [0]: https://i.imgur.com/dFvQRtE.png
  [1]: https://github.com/visionmedia/mocha/issues/960
  [2]: http://simov.github.io/loca/reporter/browser
  [3]: https://developer.chrome.com/devtools/docs/console-api
  [4]: https://developer.mozilla.org/en/docs/Tools/Web_Console#Styling_messages
  [5]: https://github.com/simov/loca/tree/master/reporter/nw