Port Messari ERC721 substream

[chillsauce]

As for making it work with Subgraphs, it's more about making it compatible with Sinks

• [x] add graph_out sink EntityChanges https://github.com/streamingfast/substreams-entity-change
• [ ] add prom_out sink `PrometheusOperations https://github.com/pinax-network/substreams-sink-prometheus.rs
• [x] support all ERC721 smart contract events https://eips.ethereum.org/EIPS/eip-721
  • [x] Transfer
  • [x] Approve
  • [x] ApprovalForAll
• [ ] Support params to filter by particular smart contract or all contracts