title: Setting title on NSMenuItem, without effect
body: <p>I'm getting an <code>NSMenuItem</code> from the <code>Main Menu</code>, with the code here : <a href="https://stackoverflow.com/questions/9852032/getting-nsmenuitem-of-nsmenu-tree-by-title">Getting NSMenuItem of NSMenu tree by title</a></p>
  
  <p>However, something strange happens :</p>
  
  <ul>
  <li>An <code>NSMenuItem</code> connected with an action : When using the sender
  property (<code>NSMenuItem</code>) and setting the title, <strong>it works</strong>. </li>
  <li><strong>BUT :</strong> When getting    the item with the function above and set the title,
  the NSMenuItem's    title does change, but the change is NOT
  reflected in the menu it    belongs to. </li>
  </ul>
  
  <p>What am I doing wrong? (I'm sure this one is really stupid... )</p>
  
  <pre><code>NSMenuItem* mi = [[core mainMenu] getItemWithPath:@"View" tag:PP_MENU_TAG_STATUSBAR];
  [mi setTitle:@"newTitle"];
  NSLog(@"mi : %@",[mi title]);
  
  // mi changes, but no changes take effect in the mainMenu
  </code></pre>