- Copy stable/10 (r259064) to releng/10.0 as part of the
10.0-RELEASE cycle.
- Update __FreeBSD_version [1]
- Set branch name to -RC1

[1] 10.0-CURRENT __FreeBSD_version value ended at '55', so
start releng/10.0 at '100' so the branch is started with
a value ending in zero.

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 Zhixiang Yu's GSoC'13 AHCI emulation:
https://wiki.freebsd.org/SummerOfCode2013/bhyveAHCI

This provides ICH8 SATA disk and ATAPI ports, selectable
via the bhyve slot command-line parameter:

SATA
-s <slot>,ahci-hd,<image-file>

ATAPI
-s <slot>,ahci-cd,<image-file>

Slight modifications by: grehan@
Approved by: re@ (blanket)
Obtained from: FreeBSD GSoC'13