Added OpenSea lazy mint support

We now support lazy mints from the popular OpenSea Shared Storefront contracts on Ethereum and Polygon.

The contract addresses are ethereum.0x495f947276749ce646f68ac8c248420045cb7b5e and polygon.0x2953399124f0cbb46d2cbacd8a89cf0599974963. To learn more lazy mints, check out this blog post on the OpenSea website:

NFTs that have been lazy minted but don't have an on-chain sale or transfer yet will show up as lazy-minted status on the NFT response. Once there is an on-chain event, this will switch to minted status like normal NFTs.

By default, lazy mint events are excluded from the Sales & Transfers endpoints, but you can opt-in by using the include_lazy_mints=1 flag to get these entries alongside normal mint, transfer, sale, and burn events. Note that they will not have a block number, since they are not associated with a block.

As of this change log post, we have the last 6 months of lazy mints loaded, with the remaining items in the process of backfilling.