Remove generated directories with 100s of files.

client/html/generated/html/interface/OptionElement.dart

Index: client/html/generated/html/interface/OptionElement.dart
diff --git a/client/html/generated/html/interface/OptionElement.dart b/client/html/generated/html/interface/OptionElement.dart
deleted file mode 100644
index 7e7a5e29a391a64183b792c0e5c9a0a63a26a144..0000000000000000000000000000000000000000
--- a/client/html/generated/html/interface/OptionElement.dart
+++ /dev/null
@@ -1,24 +0,0 @@
-// 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.
-
-// WARNING: Do not edit - generated code.
-
-interface OptionElement extends Element default _OptionElementFactoryProvider {
-
-  OptionElement([String data, String value, bool defaultSelected, bool selected]);
-
-  bool defaultSelected;
-
-  bool disabled;
-
-  final FormElement form;
-
-  final int index;
-
-  String label;
-
-  bool selected;
-
-  String value;
-}