[proposal] Myricom SNF API binding

Hello, guys,

I'm currently working on [go-snf](http://github.com/yerden/go-snf) package which wraps C binding for direct interaction with Myricom NICs (Sniffer10g SNF API). The reason for doing this, despite having Myricom NIC support in pcap, is to have all the features of SNF API with no restrictions of pcap API and that also would provide some performance benefits . I just thought that would be a nice contribution to gopacket (say, `gopacket/snf` or something). Unfortunately it would depend on proprietary library but since libpcap has this dependency, maybe it's not an issue here.

So, what do you think about eventually merging it into gopacket?