fix parent readmes

patterns/README.md

@@ -1,6 +0,0 @@
-### Relevant Articles:
-- [A Guide to the Front Controller Pattern in Java](http://www.baeldung.com/java-front-controller-pattern)
-- [Introduction to Intercepting Filter Pattern in Java](http://www.baeldung.com/intercepting-filter-pattern-in-java)
-- [Introduction to the Null Object Pattern](https://www.baeldung.com/java-null-object-pattern)
-- [The Dependency Inversion Principle in Java](https://www.baeldung.com/java-dependency-inversion-principle)
-- [Avoid Check for Null Statement in Java](https://www.baeldung.com/java-avoid-null-check)

patterns/design-patterns-2/README.md

@@ -1,3 +1,5 @@
 ### Relevant Articles
 
 - [The Mediator Pattern in Java](https://www.baeldung.com/java-mediator-pattern)
+- [Introduction to the Null Object Pattern](https://www.baeldung.com/java-null-object-pattern)
+- [Avoid Check for Null Statement in Java](https://www.baeldung.com/java-avoid-null-check)

patterns/dip/README.md

@@ -0,0 +1,3 @@
+### Relevant Articles:
+
+- [The Dependency Inversion Principle in Java](https://www.baeldung.com/java-dependency-inversion-principle)

patterns/front-controller/README.md

@@ -0,0 +1,2 @@
+### Relevant Articles:
+- [A Guide to the Front Controller Pattern in Java](http://www.baeldung.com/java-front-controller-pattern)

patterns/intercepting-filter/README.md

@@ -0,0 +1,2 @@
+### Relevant Articles:
+- [Introduction to Intercepting Filter Pattern in Java](http://www.baeldung.com/intercepting-filter-pattern-in-java)