- 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 r264400,r265836:

r264400:

NO_MAN= has been deprecated in favor of MAN= for some time, go ahead
and finish the job. ncurses is now the only Makefile in the tree that
uses it since it wasn't a simple mechanical change, and will be
addressed in a future commit.

r265836:

Remove last two NO_MAN= in the tree. In both of these cases, MAN= is
what is needed.

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

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

Fix ixp425 boot2 with ARM EABI:
- libkern is missing __aeabi_llsl, implement this by calling __ashldi3.
- Because of how the asm entry macros are defined the boot2 code
requires the unwind symbols to exist, include them in boot2.

Approved by: re (marius)

Convert old make variable modifiers :U and :L to bmake :tu and :tl.

Reviewed by: sjg

MFtbemd:

Prefer MACHNE_CPUARCH to MACHINE_ARCH in most contexts where you want
to test of all the CPUs of a given family conform.

don't hardcode cc

Submitted by: Andrey Eltsov

Add a boot loader for ixp425 based boards like the Gateworks Avila
and ADI Pronghorn Metro with Redboot on them.