Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

Make timespecadd(3) and friends public

The timespecadd(3) family of macros were imported from NetBSD back in
r35029. However, they were initially guarded by #ifdef _KERNEL. In the
meantime, we have grown at least 28 syscalls that use timespecs in some
way, leading many programs both inside and outside of the base system to
redefine those macros. It's better just to make the definitions public.

Our kernel currently defines two-argument versions of timespecadd and
timespecsub. NetBSD, OpenBSD, and FreeDesktop.org's libbsd, however, define
three-argument versions. Solaris also defines a three-argument version, but
only in its kernel. This revision changes our definition to match the
common three-argument version.

Bump _FreeBSD_version due to the breaking KPI change.

Discussed with: cem, jilles, ian, bde
Differential Revision: https://reviews.freebsd.org/D14725

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

Clean up tools in tools/tools/netrate.

- tcpconnect incorrectly uses err() in usage() with errx() semantics [1]
That produces dirty error message:
tcpconnect: usage: tcpconnect [ip]: Unknown error: 0
- 64-bit aware fixes in printf() usage [2]
o netrate/juggle: time_t has arch-dependent size
o netrate/tcpconnect: don't assume %ll has always 64bit.

PR: 146088 [1], 146086 [2] (modified)
Approved by: kib (mentor)
MFC after: 1 week

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.

Fixed error checking of pthread(3) functions.

PR: 143807
Submitted by: pluknet (partly)

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

Use $FreeBSD$ for the juggle version, rather than $P4$. This is good for
two reasons:

(1) juggle is now maintained in CVS, not P4, so the CVS revision number is
the authoritative one.
(2) Apparently $P4$ requires special handling and juggle was not marked
as needing it, resulting in problems for the P4 importer.

Requested by: gordon

Add 'juggle', a simple IPC micro-benchmark that uses various IPC types to
perform varying number of small IPC operations. It runs using a single
process and one thread, a single process and two threads, and using
multiple processes. Critical to its performance measure are the cost and
frequency of context switches, locking overhead, and threading
performance. The benchmark generates .csv output appropriate for reading
into a spreadsheet to generate summary statistics and perform statistical
tests easily.