- 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 ontop of my existing boot loader Forth code, including support for
submenus. See menusets.4th(8) for additional details including examples.

Discussed on arch and recommended for inclusion at the devsummit.

This change does not alter the appearance or user experience, only enhances
possibilities.

Reviewed by: adrian (co-mentor)
Approved by: adrian (co-mentor)