public virtual ActionResult Create(Course course)
        {
            if(ModelState.IsValid)
            {
                MvcApplication.CurrentSession.Store(course);
                MvcApplication.CurrentSession.SaveChanges();

                TempData.SetMessage("New course created");
                return RedirectToAction("Index");
            }
            else
            {
                return View(ConvertToCourseViewModel(course));
            }
        }
        CourseViewModel ConvertToCourseViewModel(Course course)
        {
            CourseViewModel courseViewModel = new CourseViewModel
            {
                Centre = MvcApplication.CurrentSession.Load<Centre>(course.CentreId),
                CentreId = course.CentreId,
                EndDate = course.EndDate,
                Id = course.Id,
                Name = course.Name,
                StartDate = course.StartDate,
                StudentIds = course.StudentIds,
                Tutor = MvcApplication.CurrentSession.Load<Person>(course.TutorId),
                TutorId = course.TutorId,
                Unit = MvcApplication.CurrentSession.Load<Unit>(course.UnitId),
                UnitId = course.UnitId,
                VerifierId = course.VerifierId
            };

            if (course.VerifierId != null)
            {
                courseViewModel.Verifier = MvcApplication.CurrentSession.Load<Person>(course.VerifierId);
            }

            courseViewModel.Students = MvcApplication.CurrentSession.Load<Person>(course.StudentIds.ToArray()).ToList();

            return courseViewModel;
        }