CVE-2017-12990/Fix printing of ISAKMPv1 Notification payload data.
The closest thing to a specification for the contents of the payload
data is draft-ietf-ipsec-notifymsg-04, and nothing in there says that it
is ever a complete ISAKMP message, so don't dissect types we don't have
specific code for as a complete ISAKMP message.
While we're at it, fix a comment, and clean up printing of V1 Nonce,
V2 Authentication payloads, and v2 Notice payloads.
This fixes an infinite loop discovered by Forcepoint's security
researchers Otto Airamo & Antti Levomäki.
Add a test using the capture file supplied by the reporter(s).