Merge branch 'features/singleton' into 'develop'

Refactor Signleton

See merge request !22

singleton/src/singleton/com/Student.java

 package singleton.com;
 
 public class Student {
-
     static Student st = new Student();
     private Student(){
         System.out.println("Simple Singleton Created ");
     }
-
     static Student getInstance(){
         return st;
     }

singleton/src/singleton/com/Test.java

 package singleton.com;
-
 public class Test {
     public static void main(String [] args){
-
         Student s1 = Student.getInstance();
         Student s2 = s1;
-
         System.out.println(s1==s2);
     }
-
 }