/**
  * Returns a list with the instructors for the provided course
  * or a message indicating there are none.
  * 
  * @since 0.1
  *  
  * @param EPCourse $course
  * 
  * @return string
  */
 protected function getInstructorsList(EPCourse $course)
 {
     $instructors = $course->getInstructors();
     if (count($instructors) > 0) {
         $instList = array();
         foreach ($instructors as $instructor) {
             $instList[] = $instructor->getUserLink() . $instructor->getToolLinks($this->getContext(), $course);
         }
         if (count($instructors) == 1) {
             return $instList[0];
         } else {
             return '<ul><li>' . implode('</li><li>', $instList) . '</li></ul>';
         }
     } else {
         return wfMsgHtml('ep-course-no-instructors');
     }
 }