docs: function matchFilterIgnoreCase(text, filter) {
          if (angular.isUndefined(text) || angular.isUndefined(filter)) {
              return true;
          }
          if (text == null || filter == null) {
              return true;
          }
          text = text.toString().trim().toLowerCase();
          filter = filter.toString().trim().toLowerCase();
          if (text.length === 0 || filter.length === 0) {
              return true;
          }
          // there can be more tokens separated by comma
          var tokens = filter.split(",");
          // filter out empty tokens, and make sure its trimmed
          tokens = tokens.filter(function (t) {
              return t.length > 0;
          }).map(function (t) {
              return t.trim();
          });
          // match if any of the tokens matches the text
          var answer = tokens.some(function (t) {
              var bool = text.indexOf(t) > -1;
              return bool;
          });
          return answer;
      }