This adds the former ports registered groups: proxy and authpf as well as
the proxy user. Make sure to run mergemaster -p in oder to complete make
installworld without errors.
This also provides the passive OS fingerprints from OpenBSD (pf.os) and an
example pf.conf.
For those who want to go without pf; it provides a NO_PF knob to make.conf.
__FreeBSD_version will be bumped soon to reflect this and to be able to
change ports accordingly.
Approved by: bms(mentor)
