Mention related efforts to establish content based identifiers

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At https://iscc.codes/concept/ several identifier systems are listed. ISCC is presented in contrast to be build on content. This is great but not a fully new idea. You should at least reference related and similar standards and best make clear how and where ISCC differs. Some pointers can be found at https://en.wikipedia.org/wiki/Content-addressable_storage. I'd at least mention Checksums (SHA), Git, and IPFS. BitTorrent also has a Merkle hash identifier feature but I think it's rarely used in the wild.