cleanup

simple_material_app/lib/main.dart

@@ -2,15 +2,20 @@ import 'package:flutter/material.dart';
 
 void main() {
   runApp(new MaterialApp(
+      // Title
       title: "Simple Material App",
+      // Home
       home: new Scaffold(
+        // Appbar
         appBar: new AppBar(
+          // Title
           title: new Text("Simple Material App"),
         ),
+        // Body
         body: new Container(
           child: new Center(
             child: new Text("Hello World!"),
           ),
         ),
       )));
-}
+}