Copy stable/9 to releng/9.3 as part of the 9.3-RELEASE cycle.

Approved by: re (implicit)
Sponsored by: The FreeBSD Foundation

Copy head to stable/9 as part of 9.0-RELEASE release cycle.

Approved by: re (implicit)

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

o Separate acl_t into internal and external representations as
required by POSIX.1e. This maintains the current 'struct acl'
in the kernel while providing the generic external acl_t
interface required to complete the ACL editing library.
o Add the acl_get_entry() function.
o Convert the existing ACL utilities, getfacl and setfacl, to
fully make use of the ACL editing library.

Obtained from: TrustedBSD Project

Prepare for the inclusion of libposix1e into libc: retire the old
Makefile, add Makefile.inc needed for libc build; add
#include "namespace.h"/#include "un-namespace.h" pairs around the
includes of sys/acl.h and sys/capability.h, and an additional underscore
in front of the functions that will be overridden in libc_r.

Approved by: rwatson
Obtained from: TrustedBSD Project

o Update copyright dates.
o Rename internal library functions so that they are prefixed with
_posix1e or _POSIX1E, removing them from the application namespace (and
potential conflict with other ACL functions elsewhere in the system).

Obtained from: TrustedBSD Project

libposix1e provides userland library calls for the POSIX.1e security
interface. This commit introduces the library, as well as a modest
subset of the ACL calls, with some modifications to support multiple
ACL semantics.

Reviewed by: eivind