Update encodings following the changes in go-ipfs

[dignifiedquire]

Ref

• remove hex encoding from flatfs go-datastore#39
• omit slash from created dskeys go-datastore#41
• encode keys to datastore with base32 standard encoding kubo#2903

New paths are /block/${base-32-std-no-padding-encoded-hash}

[daviddias]

Done on -> #76, closing this one, tracking through the PR