Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

Merge BIND 9.4.1 into main chunk.

MFC after: 2 weeks

Upgrade res_update(3) and the friends to BIND9's one excluding TSIG
support.

X-MFC after: never

Expose res_update and friends again. At least, ports/mail/spamilter
uses them.
Now, we have res_nupdate and res_nmkupdate as well, but they are
still based on our old resolver for binary backward compatibility.
So, they don't provide new features such as TSIG support.

Reported by: pointyhat via kris