lib: Automated cleanup of cdefs and other formatting

Apply the following automated changes to try to eliminate
no-longer-needed sys/cdefs.h includes as well as now-empty
blank lines in a row.

Remove /^#if.*\n#endif.*\n#include\s+<sys/cdefs.h>.*\n/
Remove /\n+#include\s+<sys/cdefs.h>.*\n+#if.*\n#endif.*\n+/
Remove /\n+#if.*\n#endif.*\n+/
Remove /^#if.*\n#endif.*\n/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/types.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/param.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/capsicum.h>/

Sponsored by: Netflix

Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

A new jail(8) with a configuration file, to replace the work currently done
by /etc/rc.d/jail.

Create the altix project branch. The altix project will add support
for the SGI Altix 350 to FreeBSD/ia64. The hardware used for porting
is a two-module system, consisting of a base compute module and a
CPU expansion module. SGI's NUMAFlex architecture can be an excellent
platform to test CPU affinity and NUMA-aware features in FreeBSD.

- Import the HEAD csup code which is the basis for the cvsmode work.

Grammar in a comment.

ANSIfy, WARNSify, CONSTify. Bit of style(9)-ify.

#include <stddef.h> for the definition of NULL instead of depending on
namespace pollution 2 layers deep in <sys/stat.h>.

Sorted includes.

Add __FBSDID()s to libutil

$Id$ -> $FreeBSD$

Now take stdio.h out of files that don't require it.

All these have to include stdio.h now.

For non-root uids, consider root-owned files also 'secure' unless otherwise
disqualified.

Summary of login.conf support changes:

o Incorporated BSDI code and enhancements, better logging for error
checking (which has been shown to be a problem, and is therefore
justified, imho); also some minor things we were missing, including
better quad_t math, which checks for under/overflows.

o setusercontext() now allows user resource limit overrides, but
does this AFTER dropping root privs, to restrict the user to
droping hard limits and set soft limits within the kernel's
allowed user limits.

o umask() only set once, and only if requested.

o add _secure_path(), and use in login.conf to guard against
symlinks etc. and non-root owned or non-user owned files being
used. Derived from BSDI contributed code.

o revamped authentication code to BSDI's latest api, which
includes deleting authenticate() and adding auth_check()
and a few other functions. This is still marked as depecated
in BSDI, but is included for completeness. No other source
in the tree uses this anyway, so it is now bracketed with
#ifdef LOGIN_CAP_AUTH which is by default not defined. Only
auth_checknologin() and auth_cat() are actually used in
module login_auth.c.

o AUTH_NONE definition removed (collided with other includes
in the tree). [bde]

o BSDI's login_getclass() now accepts a char *classname
parameter rather than struct passwd *pwd. We now do likewise,
but added login_getpwclass() for (sort of) backwards
compatiblity, namely because we handle root as a special
case for the default class. This will require quite a few
changes elsewhere in the source tree.

o We no longer pretend to support rlim_t as a long type.

o Revised code formatting to be more bsd-ish style.