support passProps in startTabBasedApp and startSingleScreenApp

README.md

@@ -152,6 +152,7 @@ Navigation.startTabBasedApp({
       screen: 'example.SecondSideMenu' // unique ID registered with Navigation.registerScreen
     }
   },
+  passProps: {}, // simple serializable object that will pass as props to all top screens (optional)
   animationType: 'slide-down' // optional, add transition animation to root change: 'none', 'slide-down', 'fade'
 });
 ```
@@ -175,6 +176,7 @@ Navigation.startSingleScreenApp({
       screen: 'example.SecondSideMenu' // unique ID registered with Navigation.registerScreen
     }
   },
+  passProps: {}, // simple serializable object that will pass as props to all top screens (optional)
   animationType: 'slide-down' // optional, add transition animation to root change: 'none', 'slide-down', 'fade'
 });
 ```

src/platformSpecific.ios.js

@@ -76,7 +76,7 @@ function startTabBasedApp(params) {
     }
   });
   ControllerRegistry.registerController(controllerID, () => Controller);
-  ControllerRegistry.setRootController(controllerID, params.animationType);
+  ControllerRegistry.setRootController(controllerID, params.animationType, params.passProps || {});
 }
 
 function startSingleScreenApp(params) {
@@ -134,7 +134,7 @@ function startSingleScreenApp(params) {
     }
   });
   ControllerRegistry.registerController(controllerID, () => Controller);
-  ControllerRegistry.setRootController(controllerID, params.animationType);
+  ControllerRegistry.setRootController(controllerID, params.animationType, params.passProps || {});
 }
 
 function _mergeScreenSpecificSettings(screenID, screenInstanceID, params) {