Sub-optimal exception with `WstxOutputProperties.P_OUTPUT_VALIDATE_NAMES`

So, setting `WstxOutputProperties.P_OUTPUT_VALIDATE_NAME` works but gives somewhat cryptic failure like

```
com.fasterxml.jackson.core.JsonGenerationException: Illegal name character ' ' (code 32)
```

which is missing full name to attempt to write (or index). It would make sense to indicate at least name (or part thereof?), index of offending character..
