- 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 r282067:

Integrate tools/regression/fifo into the FreeBSD test suite as tests/sys/fifo
and tools/regression/file into the FreeBSD test suite as tests/sys/file

Integrate tools/regression/fifo into the FreeBSD test suite as tests/sys/fifo
and tools/regression/file into the FreeBSD test suite as tests/sys/file

MFC after: 1 week

Integrate tools/regression/fifo into the FreeBSD test suite as tests/sys/fifo

Integrate more tests into the FreeBSD test suite from tools/regression, etc

Teach fifo_create regression test to also try to use mknod(2) to create
fifos, as this is required by the Single UNIX Specification, although
not currently implemented on FreeBSD.

While here, fix a bug in the directory timestamp checking test by
sleeping after querying the starting timestamp, rather than before.

Add fifo_create, a simple regression test for mkfifo(2).