Remove service-compiler related code.

pkg/servicec/lib/keyword.dart

-// Copyright (c) 2015, the Dartino 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 servicec.keyword;
-
-import "package:compiler/src/tokens/keyword.dart" as dart2js;
-
-/// Custom Keyword class for the servicec front-end.
-class Keyword extends dart2js.Keyword {
-  static const Keyword service = const Keyword("service");
-  static const Keyword struct = const Keyword("struct");
-  static const Keyword union = const Keyword("union");
-
-  static Map<String, Keyword> keywords = {
-    "service": service,
-    "struct" : struct,
-    "union" : union
-  };
-
-  const Keyword(String syntax)
-    : super(syntax);
-}