Update navigation.md. Use createStackNavigator (facebook#396)

gimenete · hramos · commit d11ccf65740b · 2018-06-15T11:37:39.000-07:00
StackNavigator is deprecated and `createStackNavigator` should be used instead.
diff --git a/docs/navigation.md b/docs/navigation.md
@@ -25,10 +25,10 @@ Then you can quickly create an app with a home screen and a profile screen:
 
 ```
 import {
-  StackNavigator,
+  createStackNavigator,
 } from 'react-navigation';
 
-const App = StackNavigator({
+const App = createStackNavigator({
   Home: { screen: HomeScreen },
   Profile: { screen: ProfileScreen },
 });
