- 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

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

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

Import byacc from invisible island, it brings us lots of compatibilities with
bison, keeping full compatibility with our previous yacc implementation.

Also bring the ability to create reentrant parser

This fix bin/140309 [1]

PR: bin/140309 [1]
Submitted by: Philippe Pepiot <ksh@philpep.org> [1]
Approved by: des (mentor)
MFC after: 1 month

Import byacc 20120115

Approved by: des (mentor)