- Copy stable/10@296371 to releng/10.3 in preparation for 10.3-RC1
builds.
- Update newvers.sh to reflect RC1.
- Update __FreeBSD_version to reflect 10.3.
- Update default pkg(8) configuration to use the quarterly branch.

Approved by: re (implicit)

MFC r258256, r258390:
Fix umastat build on present kernel.

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

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

Fix build.
- pass a format string to printf
- catch up with constifying uz_name

MFC after: 3 days

tools/umastat: more cleanups

PR: misc/146119
Submitted by: pluknet <pluknet@gmail.com>
MFC after: 1 week

tools/umastat: fix build on amd64

And perhaps other 64-bit platforms.

Submitted by: Fabian Keil <freebsd-listen@fabiankeil.de>
MFC after: 1 week

Allow to use umastat on coredumps.

Reviewed by: rwatson

Allocate proper amount of memory. Otherwise, we pass the end of a buffer,
thus having unpleasant warning. Was found by jemalloc redzone code.

Reviewed by: rwatson
Approved by: cognet (mentor)

After printing per-cpu cache contents, summarize total cached items and
entries across the caches.

Fix an off-by-one error in counting caches.

Teach umastat about the variable-length array of per-CPU caches at the end
of struct uma_zone. It is declared as an array of size [1], but then
sized at run-time by UMA to include room for mp_maxid+1 CPUs. We have to
copy the uma_zone first at the declared structure size, then check to make
sure it's not an internal zone before copying the larger size (UMA
internal zones don't use per-CPU caches). This fixes umastat for SMP.

Add a simple KVM tool to dump the kernel state of UMA, including walking
the keg/zone lists, summarizing cache state, and walking bucket lists in
each zone. I seem to get inconsistent results on SMP, possibly due to
local header problems, but it seems to work quite well on UP. This tool
requires sufficient privilege to read /dev/mem (or a core dump), and is
for debugging purposes rather than administrative monitoring purposes
(use vmstat instead).