= Add eth_node_fingerprint to block that can be imitated by both hot and cold imports
- Only sync missing blocks (blocks that are missing or don't share a fingerprint) on cold import
- Set block is_final status after import
- Allows us to fetch receipts by block and persist even when
associated transaction is unknown. (The associated transaction
can still be derived from the tx_hash column at query time, but
is an expensive operation to require for inserts).
