add: create worker account on first launch

src/main/java/com/bib/essensbestellungsverwaltung/Worker.java

@@ -1,14 +1,21 @@
 package com.bib.essensbestellungsverwaltung;
 
 /**
- * one constructor is used to create new worker the other is used to create existing worker from database
+ * one constructor is used to create new worker the other is used to create
+ * existing worker from database
+ * 
  * @author Malte Schulze Hobeling
  */
-public class Worker extends User{
+public class Worker extends User {
     public Worker(long id, String name, String firstname, String password, String email, Address address) {
         super(id, name, firstname, password, email, address);
     }
+
     public Worker(String name, String firstname, String password, String email, Address address) {
         super(name, firstname, password, email, address);
     }
+
+    public Worker(User user) {
+        super(user.getId(), user.getName(), user.getFirstname(), user.getPassword(), user.getEmail(), user.getAddress());
+    }
 }