Helper.stringToBool(): fixed switch case.

javascript/src/Helper/NameSpaceFunctions.js

@@ -37,7 +37,7 @@ QfqNS.Helper = QfqNS.Helper || {};
             case "f":
             case "false":
             case "disabled":
-            case "enable":
+            case "disable":
                 return false;
             default:
                 return false;