Corrected the date of the change log.

Author: msyk

README.md

@@ -149,7 +149,7 @@ MIT License
     Add the duplicate() method to the FileMakerLayout class. Thanks to schube.
 - 2019-09-16: [Ver.20]
     The default values  of limit and range parameters changed to 0 and both just applied for over 0 values. Thanks to schube.
-- 2019-09-16: [Ver.21]
+- 2020-08-23: [Ver.21]
     Bug fix about the field referencing of a related field without any portals. Thanks to frankeg.
     Checked on the FileMaker Server 19.