Fixed bug in tutorial with comment props

Changed the 'Author' and 'Text' props to match the sample JSON data and the data returned by the server.

Author: arbrown

site/jekyll/getting-started/tutorial.md

@@ -325,8 +325,8 @@ var CommentList = React.createClass({
   render: function() {
     var commentNodes = this.props.data.map(function (comment) {
       return (
-        <Comment author={comment.author}>
-          {comment.text}
+        <Comment author={comment.Author}>
+          {comment.Text}
         </Comment>
       );
     });