sys: Remove $FreeBSD$: two-line .h pattern

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

In ng_socket(4) expose less kernel internals to userland. This commit
breaks ABI, but makes probability of ABI breakage in future less.

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

Merge r205082, r205083 that fix 'netstat -f netgraph' functionality.

Now fix functionality of 'netstat -f netgraph' that hasn't worked
starting from netgraph import in 1999.

netstat(8) used pointer to node as node address, oops. That didn't
work, we need the node ID in brackets to successfully address a node.
We can't look into ng_node, due to inability to include netgraph/netgraph.h
in userland code. So let the node make a hint for a userland, storing
the node ID in its private data.

MFC after: 2 weeks

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

In the splnet times, netgraph was functional and synchronous. Nowadays,
an item may be queued and processed later. While this is OK for mbufs,
this is a problem for control messages.

In the framework:
- Add optional callback function pointer to an item. When item gets
applied the callback is executed from ng_apply_item().
- Add new flag NG_PROGRESS. If this flag is supplied, then return
EINPROGRESS instead of 0 in case if item failed to deliver
synchronously and was queued.
- Honor NG_PROGRESS in ng_snd_item().

In ng_socket:
- When userland sends control message add callback to the item.
- If ng_snd_item() returns EINPROGRESS, then sleep.

This change fixes possible races in ngctl(8) scripts.

Reviewed by: julian
Approved by: re (scottl)

/* -> /*- for license, minor formatting changes

Use a single style of multiple inclusion protection for Netgraph headers.

Reviewed by: archie, harti, emax

Since neither archie nor I work at Whistle any more, change our email
addresses to be the more usefu @freebsd.org ones
so we can keep getting bug-reports.
- man pages to follow..

Back out the previous change to the queue(3) interface.
It was not discussed and should probably not happen.

Requested by: msmith and others

Change the way that the queue(3) structures are declared; don't assume that
the type argument to *_HEAD and *_ENTRY is a struct.

Suggested by: phk
Reviewed by: phk
Approved by: mdodd

Move a structure Netstat needs back out to ng_socketvar.h (yech)

Re-add this till I can fix netstat to not need it.

Add the option for a socket node to shut down when the last hook
to an adjoining node is removed. Also move file scope definitions back
within the file, and remove un-needed include file.

Whistle's Netgraph link-layer (sometimes more) networking infrastructure.
Been in production for 3 years now. Gives Instant Frame relay to if_sr
and if_ar drivers, and PPPOE support soon. See:
ftp://ftp.whistle.com/pub/archie/netgraph/index.html
for on-line manual pages.

Reviewed by: Doug Rabson (dfr@freebsd.org)
Obtained from: Whistle CVS tree