- 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

Add two new utilities and two new daemons to /usr/src/usr.sbin that
are specifically used by the experimental nfsv4 subsystem.
nfscbd - The NFSv4 client callback daemon.
nfsuserd - The NFSv4 daemon that maps between user and group name
and their corresponding uid/gid numbers.
nfsdumpstate - A utility that dumps out the NFSv4 Open/Lock state.
nfsrevoke - Administratively revokes an NFSv4 client, releasing all
NFSv4 Open/Lock state it holds on the server.

Approved by: kib (mentor)