public IHttpActionResult PostSize(Size size)
        {
            if (!ModelState.IsValid)
            {
                return BadRequest(ModelState);
            }

            ent.Sizes.Add(size);
            ent.SaveChanges();

            return CreatedAtRoute("DefaultApi", new { id = size.Id }, size);
        }
        // PUT api/Size/5
        public IHttpActionResult PutSize(int id, Size size)
        {
            if (!ModelState.IsValid)
            {
                return BadRequest(ModelState);
            }

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

            ent.Entry(size).State = System.Data.Entity.EntityState.Modified;

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

            return StatusCode(HttpStatusCode.NoContent);
        }