Recursive resolution and dnslink

[ghost]

The gateway seems to resolve IPNS dnslinks only one level down. That means you can't have e.g. TXT example.com dnslink=/ipns/example.net.

This would be useful e.g. for blog.ipfs.io and ipfs.io -- right now they're separate sites, and nginx rewrites ipfs.io/blog to ipfs.io, but /ipns/ipfs.io/blog obviously doesn't work this way. We'd want to dnslink-point /ipns/blog.ipfs.io to /ipns/ipfs.io/blog.