Remove $FreeBSD$: two-line .h pattern

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

spdx: The BSD-2-Clause-FreeBSD identifier is obsolete, drop -FreeBSD

The SPDX folks have obsoleted the BSD-2-Clause-FreeBSD identifier. Catch
up to that fact and revert to their recommended match of BSD-2-Clause.

Discussed with: pfg
MFC After: 3 days
Sponsored by: Netflix

libc: further adoption of SPDX licensing ID tags.

Mainly focus on files that use BSD 2-Clause license, however the tool I
was using mis-identified many licenses so this was mostly a manual - error
prone - task.

The Software Package Data Exchange (SPDX) group provides a specification
to make it easier for automated tools to detect and summarize well known
opensource licenses. We are gradually adopting the specification, noting
that the tags are considered only advisory and do not, in any way,
superceed or replace the license texts.

resolver: preserve binary compatibility; reduce header pollution

In r289315, I added new fields to res_state. This broke binary
backward compatibility. It also broke some ports (and possibly
other code) by requiring the definition of time_t and struct timespec.

Fix these problems by moving the new fields into __res_state_ext.

Suggested by: ume
Reviewed by: ume
MFC after: 3 days
Sponsored by: Dell Inc.
Differential Revision: https://reviews.freebsd.org/D4472

resolver: automatically reload /etc/resolv.conf

On each resolver query, use stat(2) to see if the modification time
of /etc/resolv.conf has changed. If so, reload the file and reinitialize
the resolver library. However, only call stat(2) if at least two seconds
have passed since the last call to stat(2), since calling it on every
query could kill performance.

This new behavior is enabled by default. Add a "reload-period" option
to disable it or change the period of the test.

Document this behavior and option in resolv.conf(5).

Polish the man page just enough to appease igor.

https://lists.freebsd.org/pipermail/freebsd-arch/2015-October/017342.html

Reviewed by: kp, wblock
Discussed with: jilles, imp, alfred
MFC after: 1 month
Relnotes: yes
Sponsored by: Dell Inc.
Differential Revision: https://reviews.freebsd.org/D3867

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.

Nuke some compatibility crufts of resolver for 6.X and earlier.

X-MFC after: never

Don't test if RES_INIT is set to see res_state structure is
initialized. Some application may reset RES_INIT. Use the
way in __res_vinit(), instead.

- Merge our local changes.
- Exclude unnecessary functions for us.