Replace bootstrap logic with 'boot.js', use 'component/dart' mime-type and add

pkg/polymer/example/scoped_style/my_test.html

Index: pkg/polymer/example/scoped_style/my_test.html
diff --git a/pkg/polymer/example/scoped_style/my_test.html b/pkg/polymer/example/scoped_style/my_test.html
index c759c667d750a681e84ec077464b874cd4b6ef5d..ada804cf5c95c3c4f77d15f7a6a12d9ec4055f97 100644
--- a/pkg/polymer/example/scoped_style/my_test.html
+++ b/pkg/polymer/example/scoped_style/my_test.html
@@ -5,7 +5,7 @@
     </style>
     <p>Inside element, should be red</p>
   </template>
-  <script type="application/dart">
+  <script type="component/dart">
     import 'package:polymer/polymer.dart';
 
     @CustomTag('my-test')