added Date of Birth to Player.java

app/src/main/java/ch/zhaw/projekt2/turnierverwaltung/Player.java

@@ -1,10 +1,21 @@
 package ch.zhaw.projekt2.turnierverwaltung;
 
-public class Player extends Person{
+import java.util.Date;
 
+public class Player extends Person implements Participant{
 
-    public Player(String firstName, String name, String phoneNumber){
+    private Date dateOfBirth;
+
+    public Player(String firstName, String name, String phoneNumber, Date dateOfBirth){
         super(firstName, name, phoneNumber);
+        setDateOfBirth(dateOfBirth);
     }
 
+    public Date getDateOfBirth() {
+        return dateOfBirth;
+    }
+
+    public void setDateOfBirth(Date dateOfBirth) {
+        this.dateOfBirth = dateOfBirth;
+    }
 }