public IHttpActionResult PutCustomerPayment(int id, CustomerPayment customerPayment)
        {
            if (!ModelState.IsValid)
            {
                return BadRequest(ModelState);
            }

            if (id != customerPayment.Id)
            {
                return BadRequest();
            }

            db.Entry(customerPayment).State = EntityState.Modified;

            try
            {
                db.SaveChanges();
            }
            catch (DbUpdateConcurrencyException)
            {
                if (!CustomerPaymentExists(id))
                {
                    return NotFound();
                }
                else
                {
                    throw;
                }
            }

            return StatusCode(HttpStatusCode.NoContent);
        }
        public IHttpActionResult PostCustomerPayment(CustomerPayment customerPayment)
        {
            if (!ModelState.IsValid)
            {
                return BadRequest(ModelState);
            }

            db.CustomerPayments.Add(customerPayment);
            db.SaveChanges();

            return CreatedAtRoute("DefaultApi", new { id = customerPayment.Id }, customerPayment);
        }