Get rid of all the library tags.

lib/src/oauth2.dart

 // Copyright (c) 2012, 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 pub.oauth2;
-
 import 'dart:async';
 import 'dart:io';
 
 import 'package:oauth2/oauth2.dart';
 import 'package:path/path.dart' as path;
 import 'package:shelf/shelf.dart' as shelf;
 import 'package:shelf/shelf_io.dart' as shelf_io;
 
 import 'http.dart';
 import 'io.dart';
@@ skipping 195 matching lines @@
         'In a web browser, go to $authUrl\n'
         'Then click "Allow access".\n\n'
         'Waiting for your authorization...');
   });
 
   return completer.future.then((client) {
     log.message('Successfully authorized.\n');
     return client;
   });
 }