- 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

Add NetBSD's mtree to the tree and install it as nmtree as the first step
towards replacing our mtree.

Sponsored by: DARPA, AFRL
Thanks to: cristos@NetBSD for reviewing and committing my patches
wiz@NetBSD for fixing typos in my patches

Vendor import of pack_dev.* from NetBSD's mknod at 2012-12-21