public ActionResult SignUp(Volunteer volunteer, FormCollection form)
        {
            var jobRoles = SelectedJobRoles(form);
            var technologies = SelectedTechnologies(form);

            Validate(volunteer, jobRoles, technologies);

            if (ModelState.IsValid)
            {
                var volunteerRepository = new VolunteerRepository();

                volunteerRepository.Register(volunteer, jobRoles, technologies);
                volunteerRepository.Save();
                return View("Confirm");
            }

            return View(new SignUpViewModel(volunteer));
        }