[JAVA-621] Ensuring each article has its own package

* Putting test classes directly under abstractclasses package (no need
for test subpackage, we're already in test sources)

* Removed unnecessary keyword package to just let superkeyword

* Renamed scope package to variableandmethodhiding

* Renamed package basicmethods into methods

* Putting test classes directly under methodoverloadingoverriding package (no need for test subpackage, we're already in test sources)

* Moved publicmodifier package under com.baeldung as it contains code from a separate article

* Moved privatemodifier under com.baeldung as it was under an unnecessary core package

* Renamed staticdemo package into staticmodifier (was more adequate with other modifiers articles)

* Putting test classes directly under defaultstaticinterfacemethods package (no need for test subpackage, we're already in test sources)

* Moved thiskeyword package to com.baeldung instead of under keywords package

core-java-modules/core-java-lang-oop-methods/src/main/java/com/baeldung/methods/PersonName.java

@@ -1,4 +1,4 @@
-package com.baeldung.basicmethods;
+package com.baeldung.methods;
 
 import java.io.FileWriter;
 import java.io.IOException;

core-java-modules/core-java-lang-oop-methods/src/test/java/com/baeldung/methodoverloadingoverriding/MethodOverloadingUnitTest.java

@@ -1,4 +1,4 @@
-package com.baeldung.methodoverloadingoverriding.test;
+package com.baeldung.methodoverloadingoverriding;
 
 import com.baeldung.methodoverloadingoverriding.util.Multiplier;
 import org.junit.BeforeClass;

core-java-modules/core-java-lang-oop-methods/src/test/java/com/baeldung/methodoverloadingoverriding/MethodOverridingUnitTest.java

@@ -1,4 +1,4 @@
-package com.baeldung.methodoverloadingoverriding.test;
+package com.baeldung.methodoverloadingoverriding;
 
 import com.baeldung.methodoverloadingoverriding.model.Car;
 import com.baeldung.methodoverloadingoverriding.model.Vehicle;