TLS: register patterns for tls-alerts

Register patterns for when server has an alert as the first message.
icmpv6: add multicast types

Only add them to check if the code is 0 and to make sure the default
case doesn't set an 'unknown type' event.
ipv6: add support for PAD1

Support PAD1 in IPv6 HOP options header and DST options header.
tls: no event on 'new session ticket' in handshake

Don't set an event on encountering a 'new session ticket' (4) record
in the TLS handshake.