Revert "Move examples to https://github.com/react-navigation/examples"

This reverts commit 36775007b0.

examples/NavigationPlayground/js/SimpleStack.js

@@ -0,0 +1,84 @@
+/**
+ * @flow
+ */
+
+import React from 'react';
+import { Button, ScrollView, StatusBar } from 'react-native';
+import { StackNavigator, SafeAreaView } from 'react-navigation';
+import SampleText from './SampleText';
+
+const MyNavScreen = ({ navigation, banner }) => (
+  <SafeAreaView>
+    <SampleText>{banner}</SampleText>
+    <Button
+      onPress={() => navigation.navigate('Profile', { name: 'Jane' })}
+      title="Go to a profile screen"
+    />
+    <Button
+      onPress={() => navigation.navigate('Photos', { name: 'Jane' })}
+      title="Go to a photos screen"
+    />
+    <Button onPress={() => navigation.goBack(null)} title="Go back" />
+    <StatusBar barStyle="default" />
+  </SafeAreaView>
+);
+
+const MyHomeScreen = ({ navigation }) => (
+  <MyNavScreen banner="Home Screen" navigation={navigation} />
+);
+MyHomeScreen.navigationOptions = {
+  title: 'Welcome',
+};
+
+const MyPhotosScreen = ({ navigation }) => (
+  <MyNavScreen
+    banner={`${navigation.state.params.name}'s Photos`}
+    navigation={navigation}
+  />
+);
+MyPhotosScreen.navigationOptions = {
+  title: 'Photos',
+};
+
+const MyProfileScreen = ({ navigation }) => (
+  <MyNavScreen
+    banner={`${navigation.state.params.mode === 'edit'
+      ? 'Now Editing '
+      : ''}${navigation.state.params.name}'s Profile`}
+    navigation={navigation}
+  />
+);
+
+MyProfileScreen.navigationOptions = props => {
+  const { navigation } = props;
+  const { state, setParams } = navigation;
+  const { params } = state;
+  return {
+    headerTitle: `${params.name}'s Profile!`,
+    // Render a button on the right side of the header.
+    // When pressed switches the screen to edit mode.
+    headerRight: (
+      <Button
+        title={params.mode === 'edit' ? 'Done' : 'Edit'}
+        onPress={() =>
+          setParams({ mode: params.mode === 'edit' ? '' : 'edit' })}
+      />
+    ),
+  };
+};
+
+const SimpleStack = StackNavigator({
+  Home: {
+    screen: MyHomeScreen,
+  },
+  Profile: {
+    path: 'people/:name',
+    screen: MyProfileScreen,
+  },
+  Photos: {
+    path: 'photos/:name',
+    screen: MyPhotosScreen,
+  },
+});
+
+export default SimpleStack;