When reseeding the DPRNG, we're supposed to hash the current key and
some accumulated entropy twice and use that as the new key.  Due to a
typo, we were using the output of the first hash round instead of the
second.  Correct this, but eliminate temp[] since we can reuse hash[].
Also add comments explaining what is going on and why.

Noticed by:	Sami Farin <sami.farin@gmail.com>
Reviewed by:	markm@
Approved by:	so (des)
Partially fix indentation issues to improve readability helping cooperation with
Dragonfly folks

PR:		194785
Submitted by:	François Tigeot (ftigeot@wolfpond.org)
[SA-14:25] Fix kernel stack disclosure in setlogin(2) / getlogin(2).
[SA-14:26] Fix remote command execution in ftp(1).

Approved by:	so (des)
Add new libraries/utilities for data throughput visualization.
dpv(3): dialog progress view library
dpv(1): stream data from stdin or multiple paths with dialog progress view
figpar(3): configuration file parsing library

Reviews:	D714
Reviewed by:	jelischer, shurd
Discussed at:	MeetBSD California 2014 Vendor/Dev Summit
Discussed on:	-current
MFC after:	21 days
X-MFC-to:	stable/10 stable/9
vt(4): Support syscons' SC_HISTORY_SIZE to configure history size

Therefore, to set histry size to 2000 lines, add the following line to
your kernel configuration file:
    options SC_HISTORY_SIZE=2000

The default history remains at 500 lines.

MFC after:	1 week
Remove old hack abusing domattach from NFS code.

According to IANA RPC uaddr registry, there are no AFs
except IPv4 and IPv6, so it's not worth being too abstract here.

Remove ne_rtable[AF_MAX+1] and use explicit per-AF radix tries.
Use own initialization without relying on domattach code.

While I admit that this was one of the rare places in kernel
networking code which really was capable of doing multi-AF
without any AF-depended code, it is not possible anymore to
rely on dom* code.

While here, change terrifying "Invalid radix node head, rn:" message,
to different non-understandable "netcred already exists for given addr/mask",
but less terrifying. Since we know that rn_addaddr() returns NULL if
the same record already exists, we should provide more friendly error.

MFC after:	1 month
Add EXAMPLES-section entry for new key+=append syntax of sysrc(8).

MFC after:	3 days
X-MFC-to:	stable/10 stable/9
X-MFC-with:	274068
Thanks to:	@SeanChittenden
Fix build-error (pointy hat; didn't merge full up-to-date code)

MFC after:	21 days
X-MFC-to:	stable/10 stable/9
X-MFC-with:	274116
Make libdpv [dpv(3)] WARNS=6 clean for clang on -CURRENT.
NB: aka unbreak the build

Reviewed by:	shurd
MFC after:	21 days
X-MFC-to:	stable/10 stable/9
X-MFC-with:	274116 274120
Extend struct ucred with group table.

This saves one malloc + free with typical cases and better utilizes
memory.

Submitted by:	Tiwei Bie <btw mail.ustc.edu.cn> (slightly modified)
X-Additional:	JuniorJobs project
Fix buildworld by adding DPADD= to libdpv [dpv(3)] Makefile
NB: Should also address `make -j' building
Remove "+" from "+=" in assignments to DPADD/LDADD while here.
NB: Also move CFLAGS for style measure.

Reviewed by:	shurd
MFC after:	21 days
X-MFC-to:	stable/10 stable/9
X-MFC-with:	274116 274120 274121
Temporarily _disable_ compilation of dpv(3) and dpv(1).
Will revisit this to find out how to solve the ordering
issue in buildworld (potentially `make -j' specific).

Reviewed by:	shurd
Convert to use libxo.

Obtained from:	Phil Shafer <phil@juniper.net>
Sponsored by:	Juniper Networks, Inc.
Document that wc(1) supports libxo(3).
In alloc_pread() and kern_pread(), print errors only when DEBUG is
defined. An error is not fatal and is supposed to be handled by the
caller.

Obtained from:	Juniper Networks, Inc.