title: Html.EditorFor ignoring my specified class
body: <p>I have a model like:</p>
  
  <pre><code>public class MyModel {
      public string Name {get; set;}
      public DateTime StartDate {get; set;}
  }
  </code></pre>
  
  <p>Then, in my Razor view, I have this:</p>
  
  <pre><code>@Html.EditorFor(x =&gt; x.StartDate, new { @class = "input datepicker" })
  </code></pre>
  
  <p>The outputted HTML however, looks like this:</p>
  
  <pre><code>&lt;input class="text-box single-line" data-val="true" 
   data-val-required="The StartDate field is required." id="StartDate" 
   name="StartDate" type="text" value="01/01/0001 00:00:00"&gt;
  </code></pre>
  
  <p>It seems to be completely ignoring my <code>@class</code> definition (as well as adding validation stuff of its' own)</p>
  
  <p>Is there a way of making it render with my specified class?</p>