Clean up examples directory

sky/examples/stocks/lib/stock_arrow.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 'dart:math';
 import 'package:sky/framework/fn.dart';
 
 class StockArrow extends Component {
   static final Style _style = new Style('''
     width: 40px;
@@ skipping 72 matching lines @@
       style: _style,
       children: [
         new Container(
           inlineStyle: 'border-$type-color: $border',
           style: up ? _upStyle : _downStyle
         )
       ]
     );
   }
 }