Clean up snmpnetstat man page, removing some left over cruft man
original bsd netstat page.
snmpnetstat: fix usage message to be closer to reality. Fix handling of -Cp and -Cf options with new tables.
Win32: perl: Avoid transport initialization failure in Perl SNMP agents

Avoid that the followingn message is printed during startup of a Perl SNMP
agent:

netsnmp_assert s != (-1) failed ..\..\snmplib\transports\snmpUDPBaseDomain.c:484

See also commit 36a7de7230fbbbb52cc37cbbed281eb559404be9.
Merge branch 'V5-6-patches' into V5-7-patches

* V5-6-patches:
  Win32: perl: Avoid transport initialization failure in Perl SNMP agents

Conflicts:
	perl/SNMP/SNMP.xs
Win32: Unbreak the build (see also commit 253f90743)
Patch a1270: man page fixups (thnks Aleksandrs Saveljevs)
CHANGES: snmplib: Mark register_signal and unregister_signal as unused.
CHANGES: snmpd: Add a missing function declaration
Merge branch 'V5-4-patches' into V5-5-patches

* V5-4-patches:
  CHANGES: snmpd: Add a missing function declaration
Merge branch 'V5-5-patches' into V5-6-patches

* V5-5-patches:
  CHANGES: snmpd: Add a missing function declaration
Merge branch 'V5-6-patches' into V5-7-patches

* V5-6-patches:
  CHANGES: snmpd: Add a missing function declaration
CHANGES: snmpd: Remove some unused includes
Merge branch 'V5-4-patches' into V5-5-patches

* V5-4-patches:
  CHANGES: snmpd: Remove some unused includes
Merge branch 'V5-5-patches' into V5-6-patches

* V5-5-patches:
  CHANGES: snmpd: Remove some unused includes
Merge branch 'V5-6-patches' into V5-7-patches

* V5-6-patches:
  CHANGES: snmpd: Remove some unused includes
CHANGES: snmpd: Use 0 for the ignored numvars argument to netsnmp_register_mib

The numvars argument of netsnmp_register_mib is ignored if the var
argument is NULL. In order to unify this use of it with all other ones,
change it from 1 to 0
Merge branch 'V5-4-patches' into V5-5-patches

* V5-4-patches:
  CHANGES: snmpd: Use 0 for the ignored numvars argument to netsnmp_register_mib
Merge branch 'V5-5-patches' into V5-6-patches

* V5-5-patches:
  CHANGES: snmpd: Use 0 for the ignored numvars argument to netsnmp_register_mib
Merge branch 'V5-6-patches' into V5-7-patches

* V5-6-patches:
  CHANGES: snmpd: Use 0 for the ignored numvars argument to netsnmp_register_mib
snmpnetstat: fix statistics for ipv6