Roll Observatory packages and add a roll script

packages/intl/lib/date_symbol_data_http_request.dart

 // Copyright (c) 2012, 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.
 
 /**
  * This file should be imported, along with date_format.dart in order to read
  * locale data via http requests to a web server..
  */
 library date_symbol_data_http_request;
 
@@ skipping 25 matching lines @@
       locale, (l) => availableLocalesForDateFormatting.contains(l));
   return initializeIndividualLocaleDateFormatting((symbols, patterns) {
     return Future.wait(
         [symbols.initLocale(actualLocale), patterns.initLocale(actualLocale)]);
   });
 }
 
 /** Defines how new date symbol entries are created. */
 DateSymbols _createDateSymbol(Map map) =>
     new DateSymbols.deserializeFromMap(map);