public ActionResult ViewAppraisalApprovers(string FilterBy = "")
        {
            System.Configuration.Configuration rootWebConfig = System.Web.Configuration.WebConfigurationManager.OpenWebConfiguration("~/");
            System.Configuration.KeyValueConfigurationElement CurrentAppraisalPeriod = rootWebConfig.AppSettings.Settings["CurrentAppraisalPeriod"];

            List <AppraisalApproverModel> appraisalApproverModel = LINQCalls.getApproverSetupList();

            if (!String.IsNullOrEmpty(FilterBy))
            {
                appraisalApproverModel = FilterAppraisalApproverList(appraisalApproverModel, FilterBy.ToUpper());
            }
            return(View(appraisalApproverModel));
        }