title: menu_class causing a div having the class name in WordPress
body: <p>I have a script</p>
  
  <pre><code>&lt;?php 
             $menu=array(
                 'theme_location'=&gt; 'primary',
                 'menu'=&gt; '',
                 'container'        =&gt; false,
                 'container_class'  =&gt; '',
                 'container_id'     =&gt; '',
                 'menu_class'       =&gt; 'nav sf-menu',
                 'menu_id'          =&gt; '',
                 'echo'             =&gt; true,
                 'fallback_cb'      =&gt; 'wp_page_menu',
                 'before'           =&gt; '',
                 'after'            =&gt; '',
                 'link_before'      =&gt; '',
                 'link_after'       =&gt; '',
                 'items_wrap'       =&gt; '&lt;ul id="%1$s" class="%2$s"&gt;%3$s&lt;/ul&gt;',
                 'depth'            =&gt; 0,
                 'walker'           =&gt;''
             )
        ;
        wp_nav_menu($menu);?&gt;
  </code></pre>
  
  <p>It's intended to show a menu with <code>ul class="nav sf menu"</code> But the problem is that when I view source the page, I see this script:</p>
  
  <pre><code>&lt;div class="nav sf-menu"&gt;
  &lt;ul&gt;
  &lt;li class="current_page_item"&gt;&lt;
  a href="http://localhost/model.com/" title="Home"&gt;Home&lt;/a&gt;
  &lt;/li&gt;
  &lt;li class="page_item page-item-2"&gt;
  &lt;a href="http://localhost/model.com/?page_id=2"&gt;Sample Page&lt;/a&gt;
  &lt;/li&gt;
  &lt;/ul&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>How is that extra div coming on?</p>