- 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 r275170:

Convert sbin/mdconfig/tests from prove format tests to ATF format tests

As a side effect...
1. The tests now checks for the root user before continuing with kyua, which is
more visible than the test being skipped with the TAP protocol
2. The tests work with devices that aren't /dev/md0 by caching the device
attached during the test to a file, and later use the cached information to
detach the device in the cleanup routine
3. The tests no longer require perl to run

PR: 191191
Sponsored by: EMC / Isilon Storage Division

Convert sbin/mdconfig/tests from prove format tests to ATF format tests

As a side effect...
1. The tests now checks for the root user before continuing with kyua, which is
more visible than the test being skipped with the TAP protocol
2. The tests work with devices that aren't /dev/md0 by caching the device
attached during the test to a file, and later use the cached information to
detach the device in the cleanup routine
3. The tests no longer require perl to run

MFC after: 1 week
PR: 191191
Sponsored by: EMC / Isilon Storage Division