Get rid of all the library tags.

lib/src/parser.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 yaml.parser;
-
 import 'package:source_span/source_span.dart';
 import 'package:string_scanner/string_scanner.dart';
 
 import 'event.dart';
 import 'scanner.dart';
 import 'style.dart';
 import 'token.dart';
 import 'utils.dart';
 import 'yaml_document.dart';
 import 'yaml_exception.dart';
@@ skipping 790 matching lines @@
 
   /// Expect nothing.
   static const END = const _State("END");
 
   final String name;
 
   const _State(this.name);
 
   String toString() => name;
 }