title: Get Groups From OU using DirectoryServices.AccountManagement
body: <p>I'd like to use AccountManagement to list all the groups in an Organizational Unit. </p>
  
  <p>The following snippet works with DirectoryServices but I would have to instanciate GroupPrincipal with the DirectoryEntry path in the result (which feels like a dirty fix).</p>
  
  <pre><code>DirectoryEntry root = new DirectoryEntry("LDAP://OU=Marketing,OU=Operations,OU=Applications,DC=mycompany,DC=local")
          DirectorySearcher ds = new DirectorySearcher(root);
          ds.Filter = "(objectCategory=group)";
          SearchResultCollection results = ds.FindAll();
  </code></pre>
  
  <p>Has anyone an idea? </p>
  
  <p>Thanks!</p>