- 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

Replace our (un)vis(1) commands with implementations from NetBSD to
match our import of the (un)vis(3) APIs.

This adds support for multibyte encoding and the -h and -m flags which
support HTTP and MIME encoding respectively.

PR: bin/175418
Obtained from: NetBSD

Vendor import of NetBSD's unvis(1) at 2013-02-21