title: Proper ARIA handling of breadcrumb navigation
body: <p>What can be done to improve the accessibility of a breadcrumb menu similar to:</p>
  
  <pre><code>&lt;ul class="breadcrumbs" aria-label="breadcrumb navigation" role="navigation"&gt;
      &lt;li&gt;&lt;a href="~/"&gt;Home&lt;/a&gt;&lt;/li&gt;
      &lt;li&gt;&lt;a href="~/news"&gt;News&lt;/a&gt;&lt;/li&gt;
      &lt;li class="unavailable"&gt;&lt;a href="#"&gt;@Model.Title&lt;/a&gt;&lt;/li&gt;
  &lt;/ul&gt;
  </code></pre>
  
  <p>Given in this example Home is the site root, News is the first child, and the unavailable class is the current item the /news/article item.</p>
  
  <p>Is there anything that could be done to improve this such as using <code>rel</code> attributes or <code>aria-level</code> attributes?</p>