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.
Use firehol instead of all the others. AbuseIPDB.com can't be upd-
ated automatically, Abuse.ch is no longer maintained, and Spamhaus
is already in firehol.
