Remove extraneous div.messages from ctools_modal_form_render()

In ctools_modal_form_render() there is the following:

  ...
  // If there are messages for the form, render them.
  if ($messages = theme('status_messages')) {
    $output = '<div class="messages">' . $messages . '</div>' . $output;
  }

Putting the $messages inside of a div with class "messages" causes problems for any theme that has a class for .messages because you always end up with <div class="messages"><div class="messages alert">...</div></div> In this case a class definition like padding:10px; will cause a doubling of that padding... Would you be open to changing that class to "messages_wrap" (or anything else?)

I'll happily submit the patch if you're amenable...