Passive FTP

[Dag-Erling Smørgrav]

I keep forgetting that fetch(1) defaults to active FTP, because
login.conf(5) sets the FTP_PASSIVE_MODE environment variable, but every
once in a while I try to "pkg_add -r" in single-user mode or using
sudo(1) and it breaks.  I have therefore flipped the switch and made
passive FTP the default.  Those who still want active FTP (what on earth
for?) can set FTP_PASSIVE_MODE=NO in their environment.  This overrides
both the default setting and fetch(1)'s -p command-line option.

I'd like to merge this to stable/9 before 9.0 ships, so I'd appreciate
prompt feedback if anyone runs into any trouble.

I currently do *not* plan to merge this to stable/8 or any older
branches.

DES
-- 
Dag-Erling Smørgrav - des at des.no