Re-work the fail2ban and nftables interaction. Use systemd's PartOf to indicate that fail2ban is part of the nftables service, which tells systemd to propogate stop/start signals to it. Then we tell the firehol update script to restart nftables instead of reload. The different between restart and reload is meaningless for nftables but we want systemd to propagate the stop/start signals to fail2ban.