For kubenet, users should run kubelet with argument
--non-masquerade-cidr, or pods may have problem when access
"10.0.0.0/8" cidr. Also, if --pod-cidr is set outside the scope
of --non-masquerade-cidr, node will do ip masquerade for ingress
packets, which is not excepted.
This change provide a href to users, so that users knowns where to
download this loopback cin plugin. And a more accurate link about
cni configuration file is provided.
The `page.version` variable is set to a value like "1.x", while github
releases always have a version with 3 parts (like "1.x.y"). Using
`page.version` by itself in a kubernetes tree link does not work and
each of the changed links below 404s right now.
In the future, it might make sense to instead have a version variable
that includes the patch number as well.