title: MVC 4 ActionLink Dictionary htmlAttributes doesn't work
body: <p>I hope this is just a bug but figured maybe it was just me.</p>
  
  <pre><code>@Html.ActionLink("Test", "Test", "Test",
    new { id = 1 },
    new Dictionary&lt;string, object&gt; { { "class", "ui-btn-test" }, { "data-icon", "gear" } })
  </code></pre>
  
  <p>This does work but if I wanted to add further attributes I have to do it manually!</p>
  
  <pre><code>@Html.ActionLink("Test", "Test", "Test",
    new { id = 1 },
    new { @class="ui-btn-test", data_icon="gear", data_new_attr="someextra" })
  </code></pre>
  
  <p>The first doesn't work anymore and I need this one to work. The second works but don't care that it does, because I'm trying to add more attributes, object will not work unless told differently.</p>