Get rid of all the library tags.

lib/src/shelf_unmodifiable_map.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.
 
-library shelf.shelf_unmodifiable_map;
-
 import 'dart:collection';
 
 import 'package:http_parser/http_parser.dart';
 
 /// A simple wrapper over [UnmodifiableMapView] which avoids re-wrapping itself.
 class ShelfUnmodifiableMap<V> extends UnmodifiableMapView<String, V> {
   /// `true` if the key values are already lowercase.
   final bool _ignoreKeyCase;
 
   /// If [source] is a [ShelfUnmodifiableMap] with matching [ignoreKeyCase],
@@ skipping 30 matching lines @@
   ShelfUnmodifiableMap._(Map<String, V> source, this._ignoreKeyCase)
       : super(source);
 }
 
 /// A const implementation of an empty [ShelfUnmodifiableMap].
 class _EmptyShelfUnmodifiableMap<V> extends MapView<String, V>
     implements ShelfUnmodifiableMap<V> {
   bool get _ignoreKeyCase => true;
   const _EmptyShelfUnmodifiableMap() : super(const {});
 }