Roll Observatory packages and add a roll script

packages/smoke/lib/src/default_transformer.dart

 // Copyright (c) 2014, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 /// Transformer that replaces the default mirror-based implementation of smoke,
 /// so that during deploy smoke doesn't include any dependency on dart:mirrors.
 library smoke.src.default_transformer;
 
 import 'dart:async';
 import 'package:barback/barback.dart';
@@ skipping 23 matching lines @@
           .replaceAll(
               new RegExp('new Reflective[^;]*;'), 'throwNotConfiguredError();')
           .replaceAll("import 'package:smoke/mirrors.dart';", '')));
     });
   }
 }
 
 /** Transformer phases which should be applied to the smoke package. */
 List<List<Transformer>> get phasesForSmoke =>
     [[new DefaultTransformer.asPlugin()]];