title: StructLayout only for struct?
body: <p>I noticed that there are many places we have something like this:</p>
  
  <pre><code>[StructLayout(LayoutKind.Sequential, Pack = 1)]
      public class E2H_LANEFIND_DATA_T
      {
  ....
  }
  </code></pre>
  
  <p>class definition with <code>StructLayout</code>. Is that ok or <code>StructLayout</code> is only for <code>struct</code>?</p>