Remove unnecessary import from ERC721Token.sol (#855)
Remove unnecessary import from ERC721Token.sol (#855)

The DeprecatedERC721.sol isn't implemented or necessary.
OpenZeppelin/zep-solidity,OpenZeppelin/zeppelin-solidity,OpenZeppelin/openzeppelin-contracts,OpenZeppelin/openzeppelin-contracts,OpenZeppelin/zeppelin-solidity,OpenZeppelin/openzeppelin-contracts,OpenZeppelin/zep-solidity