Combine unmodifiable_collection package into collection_helpers.

pkg/collection_helpers/lib/all.dart

 // Copyright (c) 2013, 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.
 
 /**
  * Exports all the individual parts of the collection-helper library.
  *
  * The sub-libraries of this package are:
  *
  * - `algorithms.dart`: Algorithms that work on lists (shuffle, binary search
- *   and various sorting algorithms).
- * - `wrappers.dart`: Wrapper classes that delegate to a collection object.
+ *                      and various sorting algorithms).
  * - `equality.dart`: Different notions of equality of collections.
  * - `typed_buffers.dart`: Growable typed data lists.
+ * - `wrappers.dart`: Wrapper classes that delegate to a collection object.
+ *                    Includes unmodifiable views of collections.
  */
 library dart.collection_helper;
 
 export "algorithms.dart";
 export "equality.dart";
 export "typed_buffers.dart";
 export "wrappers.dart";