public Entry newEntry(Object payload) {
        Objects.requireNonNull(payload, "payload");
        return new Entry(payload);
    }
@author <a href="mailto:havardpe@yahoo-inc.com">Haavard Pettersen</a>
@author Simon Thoresen Hult
jdisc_core/src/main/java/com/yahoo/jdisc/core/ScheduledQueue.java