java.lang.IllegalArgumentException: Invalid UTF-8 char: any more "forgiveness" possible?

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- [x] Bug exists Release Version 1.2.5 ( Master Branch)
- [ ] Bug exists in MQTTv3 Client on Snapshot Version 1.2.6-SNAPSHOT (Develop Branch)
- [ ] Bug exists in MQTTv5 Client on Snapshot Version 1.2.6-SNAPSHOT (Develop Branch)

```
STACK_TRACE=java.lang.IllegalArgumentException: Invalid UTF-8 char: [0]
at org.eclipse.paho.client.mqttv3.internal.wire.MqttWireMessage.validateUTF8String(MqttWireMessage.java:407)
at org.eclipse.paho.client.mqttv3.internal.wire.MqttWireMessage.decodeUTF8(MqttWireMessage.java:365)
at org.eclipse.paho.client.mqttv3.internal.wire.MqttPublish.(MqttPublish.java:64)
at org.eclipse.paho.client.mqttv3.internal.wire.MqttWireMessage.createWireMessage(MqttWireMessage.java:207)
at org.eclipse.paho.client.mqttv3.internal.wire.MqttWireMessage.createWireMessage(MqttWireMessage.java:182)
at org.eclipse.paho.client.mqttv3.internal.wire.MqttInputStream.readMqttWireMessage(MqttInputStream.java:119)
at org.eclipse.paho.client.mqttv3.internal.CommsReceiver.run(CommsReceiver.java:137)
at java.lang.Thread.run(Thread.java:1012)
```

I use this PAHO client very happily, but now a customer got the message above. This might be a valid cause for an exception, but I don't have a change to "ignore" this crash in my Android app, so the user needs to re-install the app to get rid of the MQTT publishes he configured in my app as they will lead to the crash immediately after startup.

Is there a way to make the client code more "relaxed" about other clients publishing bad message texts to the MQTT server (I have not yet found where the code "0" is, but I guess it's a null terminator at the end of the string, which is included in the text - I don't know much about the inner format of MQTT messages and whether that's likely, but my C++ knowledge with 0-terminated strings forces that guess ;)).

A more tolerant client could help, or a way to "catch" such an event and allow the app to continue without crashing in a thread I did not create. It's OK to close the comm, of course.

I have read

> The character data in a UTF-8 encoded string MUST be well-formed UTF-8 as defined by the Unicode specification [Unicode] and restated in RFC 3629 [RFC3629]. In particular this data MUST NOT include encodings of code points between U+D800 and U+DFFF. If a Server or Client receives a Control Packet containing ill-formed UTF-8 it MUST close the Network Connection [MQTT-1.5.3-1].

so maybe the way to go is to include an option to be able to ignore the exception and become informed by some clientState event?