cordova: initial bindings for clay-mobile->cordova (native)

Also added Environment detection (kik/native/browser)
The thing is, sharing on the marketplace, in almost all cases, will be done locally. The native share call is the only one that's not. If the game is being played within Facebook, we'll want to do some facebook-specific sharing, if it's inside of Kik, we do kik specific, if it's in a browser, we do something browser specific. 

None of those are going to have the parent -> fallback model - only native will. I'd rather have determine where to have the sharing take place be all bundled in one clean conditional than try sending to native, then falling back to the same exact conditional (minus native)