public IHttpActionResult PostCustomer(Customer customer)
        {
            if (!ModelState.IsValid)
            {
                return BadRequest(ModelState);
            }

            _customerService.AddCustomer(customer);

            return CreatedAtRoute("DefaultApi", new { id = customer.ID }, customer);
        }
        // PUT api/Customer/5
        /// <summary>
        /// 
        /// </summary>
        /// <param name="id"></param>
        /// <param name="customer"></param>
        /// <returns></returns>
        public IHttpActionResult PutCustomer(int id, Customer customer)
        {
            if (!ModelState.IsValid)
            {
                return BadRequest(ModelState);
            }

            if (id != customer.ID)
            {
                return BadRequest();
            }

            _customerService.UpdateCustomer(customer);

            return StatusCode(HttpStatusCode.NoContent);
        }