ipfw: fix build

Buildbot reported:
 runmode-ipfw.c: In function 'RunModeIpsIPFWAuto':
 runmode-ipfw.c:85: error: implicit declaration of function 'LiveDeviceHasNoStats'
OpenBSD: set correct magic path

For all 5.x OpenBSDs it seems the magic path is:
    /usr/local/share/misc/magic.mgc
pfring: get vlan id from header

PF_RING is delivering the packet with VLAN header stripped. This
patch updates the code to get the information from PF_RING extended
header information.

This patch uses the new function SCKernelVersionIsAtLeast to know
that we've got a old kernel that do not strip the VLAN header from
the message before sending it to userspace.
output-json: update timestamp format

This patch updates the timestamp format used in eve loggin.
It uses a ISO 8601 comptatible string. This allow tools parsing
the output to easily detect adn/or use the timestamp.

In the EVE JSON output, the value of the timestamp key has been
changed to 'timestamp' (instead of 'time'). This allows tools
like Splunk to detect the timestamp and use it without configuration.

Logstash configuration is simple:

input {
   file {
      path => [ "/usr/local/var/log/suricata/eve.json" ]
      codec =>   json
      type => "suricata-log"
   }
}

filter {
   if [type] == "suricata-log" {
      date {
        match => [ "timestamp", "ISO8601" ]
      }
   }
}

In splunk, auto detection of the fle format is failling and it seems
you need to define a type to parse JSON in
$SPLUNK_DIR/etc/system/local/props.conf:

[suricata]
KV_MODE = json
NO_BINARY_CHECK = 1
TRUNCATE = 0

Then you can simply declare the log file in
$SPLUNK_DIR/etc/system/local/inputs.conf:

[monitor:///usr/local/var/log/suricata/eve.json]
sourcetype = suricata

In both cases the timestamp are correctly imported by
the tools.
Bug 611: fix for iponly

Fix Bug 611 for ip-only rules as well. If 'alert ip' rule has ports,
don't match on protocols that don't have ports. Like ICMP.

Bug #611.