Add --log-level command line option to filter out log messages from
lower log levels. Then fix the annoying CzechLight warning message
and useless "NACM config validation" log. Then add audit trail as
we have in netopeer2-server, and finish off by stripping redundant
fields from log message: timestamp, identity, and log level.
Fixes#892
Signed-off-by: Joachim Wiberg <troglobit@gmail.com>