Get rid of all the library tags.

lib/src/event.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.event;
-
 import 'package:source_span/source_span.dart';
 
 import 'style.dart';
 import 'yaml_document.dart';
 
 /// An event emitted by a [Parser].
 class Event {
   /// The event type.
   final EventType type;
 
@@ skipping 131 matching lines @@
 
   static const MAPPING_START = const EventType._("MAPPING_START");
   static const MAPPING_END = const EventType._("MAPPING_END");
 
   final String name;
 
   const EventType._(this.name);
 
   String toString() => name;
 }