Add logging

src/main/java/nl/connectedit/swiss/service/TournamentDivideService.java

@@ -54,6 +54,7 @@ public class TournamentDivideService {
       registrations = groupRegistrations(event.getRegistrations());
     } else {
       registrations = event.getRegistrations();
+      System.out.printf("Aantal registrations: %d", registrations.size());
     }
 
     event.setGroups(new ArrayList<>());