Prevent improper memory accesses after calling snmp_pdu_free and snmp_value_free

snmp_pdu_free: set pdu->nbindings to 0 to limit the damage that
could happen if a pdu was reused after calling the function, and
as both stack and heap allocation types are used in contrib/bsnmp
and usr.sbin/bsnmpd.

snmp_value_free: NULL out value->v.octetstring.octets after calling
free on it to prevent a double-free from occurring.

MFC after: 2 weeks

style(9): fix whitespace in pdu_encode_secparams(..)

MFC after: 3 days

style(9): clean up trailing whitespace

MFC after: 3 weeks

Be more strict about IpAddress type in snmp_value_parse(..)

- Use inet_pton with AF_INET instead of doing longhand with sscanf.
- Use gethostbyname2 with AF_INET to ensure that the hostname isn't
accidentally parsed with another address family, e.g. AF_INET6.

NB: IpAddress per RFC-2578 is IPv4 only. Work is in progress to add
the InetAddress type and friends documented in RFC-4001 and
elsewhere (which supports IPv4, IPv6, and more).

MFC after: 2 weeks

Sort #includes

No functional change

MFC after: 3 days

Fix a regression introduced in SVN r256678 that breaks USM header parsing

Reviewed by: bz@

Fix SNMP Error response PDUs and properly encode them when using v3 auth/encryption.

Reported by: harti@

Bring in a SNMP module that allows configuration of SNMPv3 Notification targets.

Sponsored by: The FreeBSD Foundation
Reviewed by: philip
Approved by: philip

Silence the compiler warnings in libbsnmp by removing several (now)
unsed parameters.

Sponsored by: The FreeBSD Foundation
Reviewed by: philip@

In bsnmpd(1) add support for SNMPv3 message processing model, including message authentication, packet encryption & view-based access control (RFC 3412, 3414, 3415).

Sponsored by: The FreeBSD Foundation
Reviewed by: philip@ (mostly)
Approved by: philip@

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.

Virgin import of bsnmpd 1.11

Virgin import of bsnmpd 1.7

Virgin import of bsnmpd 1.5a

Virgin import of bsnmp 1.4