Copy stable/10@r272459 to releng/10.1 as part of
the 10.1-RELEASE process.

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

Make hash, type and ulimit available via execve().

These are specified by POSIX but are not special builtins, and therefore
need to be available via execve() and utilities like time, nohup, xargs.
(Note that hash was moved from the XSI option to the base in the 2008
standard.)

Like most of the POSIX "regular builtin commands", these need to be executed
in a shell environment for full functionality, although they may still be of
some use outside one.

Unlike the POSIX special and regular builtin commands, POSIX does not
require these to be found before a PATH search, although that could be an
oversight.

Like some of the utilities already provided by usr.bin/alias, these may lead
to confusing results when invoked from csh(1).

Start the dreaded NOFOO -> NO_FOO conversion.

OK'ed by: core

Mark bits that do not require an object directory as such.

Fix installworld.

Submitted by: Udo Schweigert <Udo.Schweigert@siemens.com>

A little bit more thought has resulted in a generic script which can
implement any of the useless POSIX-required ``regular shell builtin''
utilities, saving one frag and one inode each. The script moves to
usr.bin/alias which is alphabetically the first of these commands.