Fix race condition in jmdns 3.4.0:

java.lang.IllegalStateException: Timer was canceled
at java.util.Timer.scheduleImpl(Timer.java:558)
at java.util.Timer.schedule(Timer.java:456)
at javax.jmdns.impl.tasks.Responder.start(Responder.java:91)
at javax.jmdns.impl.DNSTaskStarter$DNSTaskStarterImpl.startResponder(DNSTaskStarter.java:272)
at javax.jmdns.impl.JmDNSImpl.startResponder(JmDNSImpl.java:1656)
at javax.jmdns.impl.JmDNSImpl.handleQuery(JmDNSImpl.java:1457)
at javax.jmdns.impl.SocketListener.run(SocketListener.java:58)