Add encryption to IPFSStore #14
Description
dClimate would like to create encrypted Zarrs on IPFS. By doing encryption at the level of IPFSStore, we can achieve this with no changes to the HAMT code itself.
A PR that addresses this should implement this as a new class IPFSEncryptedStore that looks like IPFSStore but encrypts the data before sending to IPFS's RPC API, and then decrypts before sending this data to the HAMT.