small improvements to the logs

[eroux]

I think the logger name for TDB could be something like org.apache.jena.tdb.info instead of the current org.apache.jena.info, what do you think?

Also in the default log4j2.properties has the same logger name org.apache.jena.arq.exec under two different logger names, logger.arq-info.name and logger.arq-exec.name, I suspect this is not intended. The documentation also has this issue on logging.html

This line of documentation should have the logger name updated

The system property -Dfuseki.loglogging=true should probably be documented on https://jena.apache.org/documentation/fuseki2/fuseki-logging.html