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

pkg/polymer_expressions/example/streams/collect_key_press.html

Index: pkg/polymer_expressions/example/streams/collect_key_press.html
diff --git a/pkg/polymer_expressions/example/streams/collect_key_press.html b/pkg/polymer_expressions/example/streams/collect_key_press.html
index 48221c173f8e88394aad03881b41fb1471e6bee0..f2140564eecf3689bf3cd86a8a635c8c31991f09 100644
--- a/pkg/polymer_expressions/example/streams/collect_key_press.html
+++ b/pkg/polymer_expressions/example/streams/collect_key_press.html
@@ -25,15 +25,13 @@ BSD-style license that can be found in the LICENSE file.
       }
 
       main() {
-        mdv.initialize();
-
         var globals = {
           'keyPress': document.onKeyPress
               .map((e) => new String.fromCharCode(e.charCode)),
           'collect': collect,
         };
 
-        query('#test')
+        templateBind(query('#test'))
             ..bindingDelegate = new PolymerExpressions(globals: globals)
             ..model = null;
       }