Do name generation at client, fix localisation

Use existing group creation command

src/group.h

@@ -117,6 +117,8 @@ void RemoveVehicleFromGroup(const Vehicle *v);
 void RemoveAllGroupsForCompany(const CompanyID company);
 bool GroupIsInGroup(GroupID search, GroupID group);
 
+std::string GenerateAutoNameForVehicleGroup(const Vehicle *v);
+
 extern GroupID _new_group_id;
 
 #endif /* GROUP_H */