Remove $FreeBSD$: one-line forth tag

Remove /^\\[\s*]*\$FreeBSD\$.*$\n/

loader: Fully reset terminal settings, not just colors

Reviewed by: kevans
Reviewed by: tsoome
Approved by: mav (mentor)
MFC after: 1 week
Sponsored by: iXsystems, Inc.
Differential Revision: https://reviews.freebsd.org/D21733

Revert r332275, r332272, r332270

There's problems with them. The order of efi stuff isn't quite right,
and there's various problems. Revert until thos problems can be fixed.

Reviewed by: kevans@

loader: include efi.4th only if we do have uefi

Also simplify efi.4th.

Forth version of EFI autoresizing

r331321 delegated autoresizing to an efi-autoresizecons command that
currently is expected to be done in forth/lua prior to drawing anything
useful.

Add the Forth version of the lua addition in r331321, hook efi.4th up to be
installed.

efiboot? was written by dteske@; anything outside of that may be blamed on
me.

Move sys/boot to stand. Fix all references to new location

Sponsored by: Netflix