refactor: always use js2dart traceur and make examples run again

modules/examples/src/todo/app.es6d

@@ -13,5 +13,6 @@ export class App {
     var html = DOM.getInnerHTML(this.list);
     html += '<li>'+this.input.value+'</li>';
     DOM.setInnerHTML(this.list, html);
+    this.input.value = '';
   }
 }

modules/examples/src/todo/index.html

@@ -8,13 +8,13 @@
     <% if(type === 'dart') { %>
     <script src="main.dart" type="application/dart"></script>
     <% } else { %>
-    <script src="../../traceur-runtime.js" type="text/javascript"></script>
-    <script src="../../assert.js" type="text/javascript"></script>
+    <script src="../../../traceur-runtime.js" type="text/javascript"></script>
+    <script src="../../../assert.js" type="text/javascript"></script>
+
     <script src="app.js" type="text/javascript"></script>
     <script src="dom.js" type="text/javascript"></script>
-    <script>
-        new (System.get("examples/todo/app").App)().run();
-    </script>
+
+    <script src="main.js"></script>
     <% } %>
 </body>
 </html>

modules/examples/src/todo/main.js

@@ -0,0 +1 @@
+new (System.get("examples/src/todo/app").App)().run();