- 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

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

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

Update pf examples from OpenBSD to catch up with new stateful defaults and
other syntax changes. Move pf.conf from /etc to examples, too.

Bring in some examples (and create space for future work here):
- Add OpenBSD example rulesets as advertised in etc/pf.conf and pf.conf(5)
- Tweak the pointer to fit the FreeBSD default location share/examples/pf
- Account for the new directory in BSD.usr.dist (no hier(7) change required
as share/examples is an opaque item there).

Obtained from: OpenBSD
Reminded by: Thomas T. Veldhouse
PR: docs/71691
MFC after: 2 days