Resolve rnn from npm (#997)

* Temporarily disable shared element screens in example app

* Fix card positioning when transitioning

* resolve rnn dep from npm

example/package.json

     "react-native": "0.41.2",
     "react": "15.4.2",
     "react-native-animatable": "^1.1.0",
-    "react-native-navigation": "file:../"
+    "react-native-navigation": "next"
   },
   "devDependencies": {
     "detox": "4.x.x",