Added check for bad data (undefined tweet messages)

Accounting for bad data -- The tweets that have no messages were throwing errors in the logger and were preventing the entire list from showing. Placing the tweet texts in a string literal also helped to strip bad tweet.text inputs as well.

Author: KDCinfo

5-redux-react/src/js/components/Layout.js

@@ -27,7 +27,12 @@ export default class Layout extends React.Component {
       return <button onClick={this.fetchTweets.bind(this)}>load tweets</button>
     }
 
-    const mappedTweets = tweets.map(tweet => <li key={tweet.id}>{tweet.text}</li>)
+    const mappedTweets = tweets.map(tweet => {
+        return ((typeof(tweet.text) === 'undefined')
+            ? false
+            : <li key={tweet.id}><span>{`${tweet.text}`}</span></li>
+        )
+    })
 
     return <div>
       <h1>{user.name}</h1>