Move examples to //sky/sdk/example

sky/sdk/example/stocks2/lib/stock_row.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/painting/text_style.dart';
 import 'package:sky/rendering/box.dart';
 import 'package:sky/widgets/ink_well.dart';
 import 'package:sky/widgets/basic.dart';
 import 'package:sky/widgets/theme.dart';
 
@@ skipping 43 matching lines @@
         padding: const EdgeDims(16.0, 16.0, 20.0, 16.0),
         height: kHeight,
         decoration: const BoxDecoration(
             border: const Border(
                 bottom: const BorderSide(color: const Color(0xFFF4F4F4)))),
         child: new Flex(children)
       )
     );
   }
 }