- 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 r267265: truncate: Detect integer overflow, fix relative sizes, add tests.

The change to expand_number (r204654) broke detection of too large sizes and
relative sizes ('+'/'-').

Also add some tests.

The usr.bin/truncate/Makefile is slightly different in the MFC because
src.opts.mk does not exist in stable/10.

PR: 190735
Submitted by: Kirk Russell

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

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

Use expand_number(3) from libutil instead of home-grown function to parse
human-friendly power-of-two numbers (i.e. 2k, 5M etc).

Suggested by: many
MFC after: 1 week

Remove WARNS?=2 and -Wall. WARNS?=2 is going to be the default.

Set WARNS=2 on programs that compile cleanly with it; add $FreeBSD$
where necessary.

Submitted by: Mike Barcroft <mike@q9media.com>

Import the new truncate(1) utility.

Approved by: jdp