[JAVA-621] core-java-lang-oop-inheritance module

* Creation

* Moved code from https://www.baeldung.com/java-anonymous-classes

* Moved code from www.baeldung.com/java-polymorphism

* Moved code from www.baeldung.com/java-inheritance

* Moved code from www.baeldung.com/java-variable-method-hiding

* Moved code from https://www.baeldung.com/java-type-casting

* Moved code from https://www.baeldung.com/java-super

* Moved code from www.baeldung.com/java-interfaces

* Moved code from www.baeldung.com/java-abstract-class

* Moved code from www.baeldung.com/java-inner-interfaces

* Moved article references to the new README.md

core-java-modules/core-java-lang-oop-2/README.md

@@ -3,6 +3,5 @@
 This module contains articles about Object-oriented programming (OOP) in Java
 
 ### Relevant Articles: 
-- [Anonymous Classes in Java](https://www.baeldung.com/java-anonymous-classes)
 - [Java equals() and hashCode() Contracts](https://www.baeldung.com/java-equals-hashcode-contracts)
 - [[<-- Prev]](/core-java-modules/core-java-lang-oop)[[More -->]](/core-java-modules/core-java-lang-oop-3)

core-java-modules/core-java-lang-oop-2/src/main/java/com/baeldung/anonymous/Book.java

@@ -1,15 +0,0 @@
-package com.baeldung.anonymous;
-
-public class Book {
-
-    final String title;
-    
-    public Book(String title) {
-        this.title = title;
-    }
-    
-    public String description() {
-        return "Title: " + title;
-    }
-
-}

core-java-modules/core-java-lang-oop-2/src/main/java/com/baeldung/anonymous/Main.java

@@ -1,64 +0,0 @@
-package com.baeldung.anonymous;
-
-import java.util.ArrayList;
-import java.util.List;
-
-/**
- * Code snippet that illustrates the usage of anonymous classes.
- * 
- * Note that use of Runnable instances in this example does not demonstrate their
- * common use.
- * 
- * @author A. Shcherbakov
- *
- */
-public class Main {
-
-    public static void main(String[] args) {
-        final List<Runnable> actions = new ArrayList<Runnable>(2);
-
-        Runnable action = new Runnable() {
-            @Override
-            public void run() {
-                System.out.println("Hello from runnable.");
-            }
-
-        };
-        actions.add(action);
-
-        Book book = new Book("Design Patterns") {
-            @Override
-            public String description() {
-                return "Famous GoF book.";
-            }
-        };
-
-        System.out.println(String.format("Title: %s, description: %s", book.title, book.description()));
-
-        actions.add(new Runnable() {
-            @Override
-            public void run() {
-                System.out.println("Hello from runnable #2.");
-
-            }
-        });
-
-        int count = 1;
-
-        Runnable action2 = new Runnable() {
-            static final int x = 0;
-            // static int y = 0;
-
-            @Override
-            public void run() {
-                System.out.println(String.format("Runnable with captured variables: count = %s, x = %s", count, x));
-            }
-        };
-        actions.add(action2);
-
-        for (Runnable a : actions) {
-            a.run();
-        }
-    }
-
-}