public static void UpdateSkillLevel(HttpRequestBase req, HttpResponseBase res)
        {
            var id     = int.Parse(req["id"]);
            var level  = int.Parse(req["level"]);
            var result = _employeeLogic.UpdateSkill(id, level);

            if (result)
            {
                res.Write(JsonConvert.SerializeObject(new RequestResult("Success", "Level has been changed.")));
            }
            else
            {
                res.Write(JsonConvert.SerializeObject(new RequestResult("Error", "Cannot change level.")));
            }
        }