* 1. `dag-pb` is protobuf, which decodes to `merkledag.ProtoNode`. It usually (always?) contains UnixFSv1 protobuf, right?
2. `dag-cbor` is CBOR, which decodes to `cbornode.Node`. What does it contain? I guess UnixFSv1 now, maybe UnixFSv2 later?
3. `raw` is just raw bytes, without encoding. For IPFS this is usually file contents, right?
4. How does `raw` relate to `identity`?
5. How do `dag-pb` and `dag-cbor` relate to `protobuf` and `cbor`?