- Copy stable/10@285827 to releng/10.2 in preparation for 10.2-RC1
builds.
- Update newvers.sh to reflect RC1.
- Update __FreeBSD_version to reflect 10.2.
- Update default pkg(8) configuration to use the quarterly branch.[1]

Discussed with: re, portmgr [1]
Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

MFC r278704:

Unbreak rcorder when MK_UNBOUND == no by moving local_unbound from REQUIRE:
in NETWORKING to BEFORE: in the script

Copy head (r256279) to stable/10 as part of the 10.0-RELEASE cycle.

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

Move local_unbound up in the rc order.

Approved by: re (blanket)

Add a setup script for unbound(8) called local-unbound-setup. It
generates a configuration suitable for running unbound as a caching
forwarding resolver, and configures resolvconf(8) to update unbound's
list of forwarders in addition to /etc/resolv.conf. The initial list
is taken from the existing resolv.conf, which is rewritten to point to
localhost. Alternatively, a list of forwarders can be provided on the
command line.

To assist this script, add an rc.subr command called "enabled" which
does nothing except return 0 if the service is enabled and 1 if it is
not, without going through the usual checks. We should consider doing
the same for "status", which is currently pointless.

Add an rc script for unbound, called local_unbound. If there is no
configuration file, the rc script runs local-unbound-setup to generate
one.

Note that these scripts place the unbound configuration files in
/var/unbound rather than /etc/unbound. This is necessary so that
unbound can reload its configuration while chrooted. We should
probably provide symlinks in /etc.

Approved by: re (blanket)