Rename mdv -> template_binding, remove experiemntal apis from dart:html

pkg/mdv/lib/src/text.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.
-
-part of mdv;
-
-/** Extensions to the [Text] API. */
-class _TextExtension extends _NodeExtension {
-  _TextExtension(Text node) : super(node);
-
-  NodeBinding createBinding(String name, model, String path) {
-    if (name == 'text') return new _TextBinding(node, model, path);
-    return super.createBinding(name, model, path);
-  }
-}
-
-class _TextBinding extends NodeBinding {
-  _TextBinding(node, model, path) : super(node, 'text', model, path);
-
-  void boundValueChanged(newValue) {
-    node.text = sanitizeBoundValue(newValue);
-  }
-}