public async Task<IHttpActionResult> PostCategory(Category category)
        {
            if (!ModelState.IsValid)
            {
                return BadRequest(ModelState);
            }

            db.Category.Add(category);

            try
            {
                await db.SaveChangesAsync();
            }
            catch (DbUpdateException)
            {
                if (CategoryExists(category.SmallCategoryName))
                {
                    return Conflict();
                }
                else
                {
                    throw;
                }
            }

            return CreatedAtRoute("DefaultApi", new { id = category.SmallCategoryName }, category);
        }
        public async Task<IHttpActionResult> PutCategory(string id, Category category)
        {
            if (!ModelState.IsValid)
            {
                return BadRequest(ModelState);
            }

            if (id != category.SmallCategoryName)
            {
                return BadRequest();
            }

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

            try
            {
                await db.SaveChangesAsync();
            }
            catch (DbUpdateConcurrencyException)
            {
                if (!CategoryExists(id))
                {
                    return NotFound();
                }
                else
                {
                    throw;
                }
            }

            return StatusCode(HttpStatusCode.NoContent);
        }