Remove uses of Options from pkg, samples, tests, and third_party directories.

pkg/watcher/example/watch.dart

 // Copyright (c) 2013, 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.
 
 /// Watches the given directory and prints each modification to it.
 library watch;
 
 import 'dart:io';
 
 import 'package:path/path.dart' as p;
 import 'package:watcher/watcher.dart';
 
-main() {
-  var args = new Options().arguments;
-  if (args.length != 1) {
+main(List<String> arguments) {
+  if (arguments.length != 1) {
     print("Usage: watch <directory path>");
     return;
   }
 
-  var watcher = new DirectoryWatcher(p.absolute(args[0]));
+  var watcher = new DirectoryWatcher(p.absolute(arguments[0]));
   watcher.events.listen((event) {
     print(event);
   });
-}
+}