dns/bind* ports overwriting conf files

[Doug Barton]

While looking at the UPDATING entry for the bdb mess (more on that 
later) I happened to see this:

20131209:
   AFFECTS: users of dns/bind96, dns/bind98 and bind99 on FreeBSD 10.0
   AUTHOR: erwin at FreeBSD.org

   Bind versions before 9.6.3.2.ESV.R10_2, 9.8.6_2, and 9.9.4_2 on
   FreeBSD 10.0 will replace named.conf on upgrade.  Make sure to
   backup any local changes before upgrading to the _2 versions.

This is not Ok. FreeBSD ports are NEVER supposed to blindly overwrite 
config files. Please fix this so that it confirms to over a decade of 
policy that FreeBSD ports users should be able to safely depend on.

Doug