- 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 r268993, r268893, r268994, plus partial r264070, r264082

Fix C++ exception handling for ARM EABI.

Just the part of r264070 that creates the FBSD_1.4 namespace in libc
is hand-applied, and then r264082 which creates the Versions.def entry
is MFC'd.

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

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

Add a FBSD_1.3 namespace for FreeBSD 10.

Bump our namespace version for 9.0.

Add a comment about keeping the private namespace at the end of
the dependency chain.

Keep versions on a dependency chain to exclude even remote possiblity
of private version ever getting index 2.

Add a comment stating not to bump the FBSDprivate version.

Don't inherit the public namespace from the private namespace.

Retire the __fgetcookie(), __fgetpendout(), and __fsetfileno() accessors
as we aren't hiding FILE's internals anymore.

Add __fgetcookie(), __fgetpendout() and __fsetfileno() to the private
name space.

Increment the version namespace for 8.0-current. New symbols and
symbols whose ABI has changed should be added to FBSD_1.1.

Make sure FBSDprivate_1.0 is located at the end of the version
inheritance chain.

Number the private version namespace in case we ever want to have
compatibility between versions (as we do for the public namespace).

Add symbol maps and initial symbol version definitions to libc.

Reviewed by: davidxu