Update onNewIntent to override. Update example project to RN 0.31

Author: cbrevik

android/src/main/java/com/idehub/Billing/InAppBillingBridge.java

@@ -368,7 +368,7 @@ public void onActivityResult(final int requestCode, final int resultCode, final
             bp.handleActivityResult(requestCode, resultCode, intent);
     }
 
-  
+    @Override
     public void onNewIntent(Intent intent){
 
     }

example/package.json

@@ -7,7 +7,7 @@
   },
   "dependencies": {
     "react": "15.2.1",
-    "react-native": "0.29.2",
+    "react-native": "0.31.0",
     "react-native-billing": "file:../"
   }
 }