try to make naming more consistent

src/main/java/mops/gruppen2/domain/User.java

@@ -1,14 +1,13 @@
 package mops.gruppen2.domain;
 
+import lombok.AllArgsConstructor;
 import lombok.Data;
 
-import java.util.List;
-
 @Data
+@AllArgsConstructor
 public class User {
-	String id;
-	String vorname;
-	String nachname;
+	String user_id;
+	String givenname;
+	String familyname;
 	String email;
-	List<Group> gruppen;
 }