Add support for the 2016 EC2 metadata releases
Add support for the 2016 EC2 metadata releases

This adds the following data:

network/interfaces/macs/mac/ipv6s
network/interfaces/macs/mac/subnet-ipv6-cidr-blocks
network/interfaces/macs/mac/vpc-ipv4-cidr-blocks
network/interfaces/macs/mac/vpc-ipv6-cidr-blocks

Signed-off-by: Tim Smith <764ef62106582a09ed09dfa0b6bff7c05fd7d1e4@chef.io>

mattray/ohai,higanworks/ohai,jaymzh/ohai,chef/ohai,jseely/ohai,chef/ohai,higanworks/ohai,jaymzh/ohai,jseely/ohai,mattray/ohai