Update pub to use new import syntax.

utils/pub/io.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.
 
 /**
  * Helper functionality to make working with IO easier.
  */
-#library('io');
+library io;
 
-#import('dart:io');
-#import('dart:isolate');
-#import('dart:uri');
+import 'dart:io';
+import 'dart:isolate';
+import 'dart:uri';
 
-#import('utils.dart');
+import 'utils.dart';
 
 bool _isGitInstalledCache;
 
 /// The cached Git command.
 String _gitCommandCache;
 
 /** Gets the current working directory. */
 String get workingDir => new File('.').fullPathSync();
 
 /**
@@ skipping 749 matching lines @@
   return new Directory(entry);
 }
 
 /**
  * Gets a [Uri] for [uri], which can either already be one, or be a [String].
  */
 Uri _getUri(uri) {
   if (uri is Uri) return uri;
   return new Uri.fromString(uri);
 }