Add include_tags and exclude_tags config fields.

test/runner/configuration/top_level_test.dart

 // Copyright (c) 2016, 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.
 
 @TestOn("vm")
 
 import 'dart:convert';
 
 import 'package:path/path.dart' as p;
 import 'package:scheduled_test/descriptor.dart' as d;
@@ skipping 356 matching lines @@
       void main() {
         test("success", () => new Future.delayed(Duration.ZERO));
       }
     """).create();
 
     var test = runTest(["--timeout=none", "test.dart"]);
     test.stdout.expect(consumeThrough(contains("All tests passed!")));
     test.shouldExit(0);
   });
 
-
   test("uses the specified regexp names", () {
     d.file("dart_test.yaml", JSON.encode({
       "names": ["z[ia]p", "a"]
     })).create();
 
     d.file("test.dart", """
       import 'package:test/test.dart';
 
       void main() {
         test("zip", () {});
@@ skipping 102 matching lines @@
           test("failure", () => throw "oh no");
         }
       """)
     ]).create();
 
     var test = runTest([]);
     test.stdout.expect(consumeThrough(contains('All tests passed!')));
     test.shouldExit(0);
   });
 }