Updating the samples page to reflect the examples that have been retired.

src/site/samples/todo_with_delete/index.markdown

----
-layout: default
-title: Removing Elements from the DOM
-live_example_url: /docs/tutorials/remove-elements/examples/todo_with_delete/todo_with_delete.html
-header:
-  css: ["/samples/samples.css"]
----
-
-## {{ page.title }}
-
-Enter text in the input field and press return. Point the mouse cursor at an
-item in the list. Click the item to delete it.
-
-This app shows how to programmatically remove an element from the DOM.
-
-In this example, when you click an item in the list, the event handler for
-the <li> element removes itself from the DOM tree. When the DOM tree
-changes, the web page refreshes.
-
-Read this [tutorial](/docs/tutorials/remove-elements/) for
-more detail, or read the
-[source](https://github.com/dart-lang/dart-tutorials-samples/tree/master/todo_with_delete).
-
-<iframe class="running-app-frame"
-        style="height:400px;width:100%;"
-        src="{{page.live_example_url}}">
-</iframe>
-
-See all [samples](/samples/).