added article link

thombergs · web-flow · commit 88e49ebda5d4 · 2018-05-04T20:53:53.000+02:00
diff --git a/core-java/README.md b/core-java/README.md
@@ -146,3 +146,4 @@
 - [Introduction to SSL in Java](http://www.baeldung.com/java-ssl)
 - [Java KeyStore API](http://www.baeldung.com/java-keystore)
 - [Double-Checked Locking with Singleton](http://www.baeldung.com/java-singleton-double-checked-locking)
+- [Guide to Java Clock Class](http://www.baeldung.com/java-clock)
