Add ERC1155Holder to prevent Packs.reveal abuse

[ScreamingHawk]

Adds ERC1155Holder, which accepts ERC1155 tokens and allows them to be claimed by the claimant encoded in the data.

This prevents the user from denying certain tokens when interacting with packs.reveal(), which would allow them to retry for a better reveal.

Includes some trivial optimizations to keep bytecode size within the limits.
This change does not require any ABI updates.

This includes NC-03, flipping the _commitment nested mapping keys.

Future optimizations if we can reduce bytecode size further:

• Always attempt transfer to the recipient, only use the ERC1155Holder as a fallback
• Use abi.encodePacked(recipient)
• Add updateERC1155Holder() to configure the holder after deployment