public IHttpActionResult AddCourse(Course course)
        {
            if (course == null
               || string.IsNullOrWhiteSpace(course.Name)
               || course.StartDate > course.EndDate
               || string.IsNullOrWhiteSpace(course.TemplateID)
               || course.ID <= 0)
            {
                return StatusCode(HttpStatusCode.PreconditionFailed);
            }

            foreach (Course c in _courses)
            {
                if (c.ID == course.ID)
                {
                    return Conflict();
                }
            }
            _courses.Add(course);

            var location = Url.Link("GetCourse", new { id = course.ID });
            return Created(location, course);
        }
        public IHttpActionResult UpdateCourse(Course course)
        {
            if (course == null
               || string.IsNullOrWhiteSpace(course.Name)
               || course.StartDate > course.EndDate
               || string.IsNullOrWhiteSpace(course.TemplateID)
               || course.ID <= 0)
            {
                return StatusCode(HttpStatusCode.PreconditionFailed);
            }

            foreach (Course c in _courses)
            {
                if (c.ID == course.ID)
                {
                    c.Name = course.Name;
                    c.EndDate = course.EndDate;
                    c.StartDate = course.StartDate;
                    c.TemplateID = course.TemplateID;

                    return StatusCode(HttpStatusCode.NoContent);
                }
            }
            return StatusCode(HttpStatusCode.NotFound);
        }