Roll Observatory packages and add a roll script

packages/smoke/lib/mirrors.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.
 
 /// Implementation of the smoke services using mirrors.
 library smoke.mirrors;
 
 import 'dart:mirrors';
 import 'package:smoke/smoke.dart';
 import 'package:logging/logging.dart';
@@ skipping 304 matching lines @@
   String toString() => (new StringBuffer()
     ..write('(mirror-based-declaration ')
     ..write(name)
     ..write(
         isField ? ' (field) ' : (isProperty ? ' (property) ' : ' (method) '))
     ..write(isFinal ? 'final ' : '')
     ..write(isStatic ? 'static ' : '')
     ..write(annotations)
     ..write(')')).toString();
 }