Roll Observatory packages and add a roll script

packages/charted/lib/charts/data_transformers/transpose_transformer.dart

 /*
  * Copyright 2014 Google Inc. All rights reserved.
  *
  * Use of this source code is governed by a BSD-style
  * license that can be found in the LICENSE file or at
  * https://developers.google.com/open-source/licenses/bsd
  */
 
 part of charted.charts;
 
@@ skipping 105 matching lines @@
     // Construct new ColumnSpaces base on the label column.
     for (var label in columnLabels) {
       columns.add(new ChartColumnSpec(type: type, label: label,
           formatter: formatter));
     }
     columns.insert(_labelColumn,
         new ChartColumnSpec(type: ChartColumnSpec.TYPE_STRING, label:
         _data.columns.elementAt(_labelColumn).label));
   }
 }