Update Netflow v9 and IPFIX Information Elements list in YAML files

[jorritfolmer]

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We don't currently support all the Information Elements currently assigned by IANA.

An overview can currently be found in issues #83 and #84

TODO:

1. Update netflow.yaml to include all the IE's from the IANA list
2. Update ipfix.uaml to include all the IE's from the IANA list

Volunteers?

[jorritfolmer]

netflow.yaml is now updated to the same level as ipfix.yaml. Both lists should still be updated to the current IANA list.