add the revision number to the name filter, salted with the AES key for the node.

add some string to a name filter.

Copy blocks from src to dst.

create bare name filter with a single key.

root key should be the identity bare name filter.

parent is the "super" constructor arg.

NodeStore extracts a private store from a wnfs.Node.

saturate the filter to 320 bits and hash it with sha256 to give the private name that a node will be stored in the MMPT with.

A CBOR-marshalable byte array.