Split layout2.dart into several files

sky/examples/stocks2/lib/stock_app.dart

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // import 'package:sky/framework/components2/tool_bar.dart';
 // import 'package:sky/framework/components2/drawer.dart';
 // import 'package:sky/framework/components2/drawer_header.dart';
 // import 'package:sky/framework/components2/floating_action_button.dart';
 // import 'package:sky/framework/components2/icon.dart';
 // import 'package:sky/framework/components2/icon_button.dart';
 // import 'package:sky/framework/components2/input.dart';
 // import 'package:sky/framework/components2/menu_divider.dart';
 // import 'package:sky/framework/components2/menu_item.dart';
 // import 'package:sky/framework/components2/modal_overlay.dart';
 // import 'package:sky/framework/components2/popup_menu.dart';
 // import 'package:sky/framework/components2/radio.dart';
 import 'package:sky/framework/components2/scaffold.dart';
 import 'package:sky/framework/fn2.dart';
 import 'package:sky/framework/theme/typography.dart' as typography;
 import 'package:sky/framework/theme/colors.dart';
 import 'stock_data.dart';
 // import 'stock_list.dart';
 // import 'stock_menu.dart';
 
 import 'dart:async';
-import 'package:sky/framework/layout2.dart';
 
 enum StockMode { Optimistic, Pessimistic }
 
 class StocksApp extends App {
 
   // static final Style _toolBarStyle = new Style('''
   //   background-color: ${Purple[500]};''');
 
   // static final Style _searchBarStyle = new Style('''
   //   background-color: ${Grey[50]};''');
@@ skipping 184 matching lines @@
     //   drawer: _drawerShowing ? buildDrawer() : null,
     //   overlays: overlays
     );
   }
 }
 
 void main() {
   print("starting stocks app!");
   new StocksApp();
 }