BFK.de depricated

[silascutler]

The BFK.de Passive DNS may be deprecated. When called, the following message is displayed:
Due to the EU GDPR policy, this service has been shut down until further notice.

Traceback (most recent call last):
        9: from /usr/local/bin/pdnstool:23:in `<main>'
        8: from /usr/local/bin/pdnstool:23:in `load'
        7: from /var/lib/gems/2.5.0/gems/passivedns-client-2.1.11/bin/pdnstool:5:in `<top (required)>'
        6: from /var/lib/gems/2.5.0/gems/passivedns-client-2.1.11/lib/passivedns/client/cli.rb:274:in `run'
        5: from /var/lib/gems/2.5.0/gems/passivedns-client-2.1.11/lib/passivedns/client/cli.rb:274:in `new'
        4: from /var/lib/gems/2.5.0/gems/passivedns-client-2.1.11/lib/passivedns/client.rb:80:in `initialize'
        3: from /var/lib/gems/2.5.0/gems/passivedns-client-2.1.11/lib/passivedns/client.rb:80:in `each'
        2: from /var/lib/gems/2.5.0/gems/passivedns-client-2.1.11/lib/passivedns/client.rb:82:in `block in initialize'
        1: from /var/lib/gems/2.5.0/gems/passivedns-client-2.1.11/lib/passivedns/client.rb:82:in `new'
/var/lib/gems/2.5.0/gems/passivedns-client-2.1.11/lib/passivedns/client/provider/bfk.rb:41:in `initialize': Due to the EU GDPR policy, this service has been shut down until further notice. (RuntimeError)

It's recommended we remove this module.