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

Renumber clauses to reduce diffs to other versions

NetBSD, OpenBSD, and Android's Bionic number the clauses 1 through 3,
so follow suit to make comparison easier.

- ANSIfy function definitions
- use nul when we are looking for a terminating character where appropriate

Approved by: imp

Per Regents of the University of Calfornia letter, remove advertising
clause.

# If I've done so improperly on a file, please let me know.

Fix the NetBSD RCS id's on these files; somehow they were initially
committed with the tags unexpanded.

Remove unnecessary #include <assert.h>; it was used to bring in the
_DIAGASSERT macro on NetBSD, but we don't need it.

Fix the style of the SCM ID's.
I believe have made all of libc .c's as consistent as possible.

rcsid[]->__FBSDID

Make the rcsid and FreeBSD IDs more sane in the wcs* and wmem* files.
Do the same for the non-wcs*/wmem* files while I'm here.

Unbreak world; _DIAGASSERT macro is not available in FreeBSD.

initial import of locale insensitive wcs* and wmem* functions.

Obtained from: NetBSD and Citrus.