Library throw exception in rx flow

Actually we log exceptions from library. What fix you suggest?

```
java.io.IOException: Operation not permitted
at java.net.PlainDatagramSocketImpl.send(PlainDatagramSocketImpl.java)
at java.net.DatagramSocket.send(DatagramSocket.java:696)
at com.instacart.library.truetime.SntpClient.requestTime(SntpClient.java:116)
at com.instacart.library.truetime.TrueTime.requestTime(TrueTime.java:133)
at com.instacart.library.truetime.TrueTimeRx$4$1$2.subscribe(TrueTimeRx.java:211)
at io.reactivex.internal.operators.flowable.FlowableCreate.subscribeActual(FlowableCreate.java:72)
at io.reactivex.Flowable.subscribe(Flowable.java:14409)
at io.reactivex.Flowable.subscribe(Flowable.java:14356)
at io.reactivex.internal.operators.flowable.FlowableSubscribeOn$SubscribeOnSubscriber.run(FlowableSubscribeOn.java:82)
at io.reactivex.internal.schedulers.ScheduledRunnable.run(ScheduledRunnable.java:66)
at io.reactivex.internal.schedulers.ScheduledRunnable.call(ScheduledRunnable.java:57)
at java.util.concurrent.FutureTask.run(FutureTask.java:237)
at java.util.concurrent.ScheduledThreadPoolExecutor$ScheduledFutureTask.run(ScheduledThreadPoolExecutor.java:272)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1133)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:607)
at java.lang.Thread.run(Thread.java:761)
```