Remove $FreeBSD$: two-line nroff pattern

Remove /^\.\\"\n\.\\"\s*\$FreeBSD\$$\n/

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

mdoc: order prologue macros consistently by Dd/Dt/Os

Although groff_mdoc(7) gives another impression, this is the ordering
most widely used and also required by mdocml/mandoc.

Reviewed by: ru
Approved by: philip, ed (mentors)

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.

Expand *n't contractions.

Added the EXIT STATUS section where appropriate.

Mechanically kill hard sentence breaks.

Use `The .Nm utility'

mdoc(7) police: use plain text parentheses with plain text blocks.

Implement the -I option that uses the FD_READID ioctl in order to read
sector ID fields from a floppy, and display them.

Fix man page markup.

Submitted by: ru

Initial import of fdread(1), a logical counterpart to fdwrite(1).

Its main purpose is to adapt automatically to the floppy parameters
(in particular the track size for efficient reading), and to allow a
simple error recovery for CRC-errored sectors. Requires the newly
added fdc(4) options.