Fix typo and add comments to the example app

docs/Tutorial.md

@@ -198,7 +198,7 @@ Add the following constants to the top of the file (typically below the requires
 
 ```javascript
 /**
- * For quota reasons we replaced the Roten Tomatoes' API with a sample data of
+ * For quota reasons we replaced the Rotten Tomatoes' API with a sample data of
  * their very own API that lives in React Native's Gihub repo.
  */
 var REQUEST_URL = 'https://raw.githubusercontent.com/facebook/react-native/master/docs/MoviesExample.json';