graylog-plugin-netflow Support for IPFIX

It would be awesome if you could add IPFIX support to this plugin. As it is a "open version of NetFlow" i think this is the right place for it. "NetFlow and IPFIX are flow or messaging technologies that are nearly identical. IPFIX is the official IETF standard and considered by some to be NetFlow v10. IPFIX allows for variable length strings and opens the technology up to allow vendors other than Cisco to export unique details about the traffic passing through their hardware." source: https://www.ipfixcollector.com/ To get a quick overview what it is: https://en.wikipedia.org/wiki/IP_Flow_Information_Export IPFIX compared to NetFlow v9: https://www.plixer.com/blog/netflow/what-is-ipfix-vs-netflow-v9/ related issue for logstash with further information for implementation stuff: https://github.com/logstash-plugins/logstash-codec-netflow/pull/10 Eventually helpful ipfix library: https://github.com/cameronkerrnz/libipfix