GPAUDITLOGGING-65 Configuration option for logging full class name

In my opinion, true would be the sensible default value for logFullClassName. As mentioned in GPAUDITLOGGING-65, previous versions of the plugin logged the full class name. Also, Grails allows multiple domain classes with the same name in different packages, we should be able to distinguish them using the default audit logging configuration.

But that's just my opinion, I'm not really too concerned with the default value as long as I can configure it.