For now this mainly provides an example config and confirms that
log-validator can start up and shut down cleanly, as well as provide a
stat indicating how many log lines it has handled.
This introduces a syslog config to the boulder-tools image that will write
logs to /var/log/program.log. It also tweaks the various .json config
files so they have non-default syslogLevel, to ensure they actually
write something for log-validator to verify.