- 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 262989, 263210, 263230, 263231, 263239, 263242, 263243,

Export _libc_arm_fpu_present as a private symbol to be used by other
system libraries, for example libm.

On armv6 access both the softfloat and, when available, the vfp to get and
set the floating-point environment.

Build fenv-vfp.c with the softfp float abi. Without this gcc generates an
incorrect assembly file that doesn't allow for vfp instructions.

Only build the vfp/softfp switching code on armv6 as we don't support vfp
on anything earlier than this. This should fix the armeb and arm builds
when using gcc.

Add an optimised version of the float and double helper functions.

On armv6 access both the softfloat and, when available, the vfp to get and
set the floating-point environment.