erc20 balance

usage:
    ctc erc20 balance ERC20_ADDRESS WALLET_ADDRESS [options]

description:
    output an ERC20 balance

examples:
    ctc erc20 balance 0x956f47f50a910163d8bf957cf5846d573e7f87ca 0x9928e4046d7c6513326ccea028cd3e7a91c7590a
    ctc erc20 balance 0x956f47f50a910163d8bf957cf5846d573e7f87ca 0x9928e4046d7c6513326ccea028cd3e7a91c7590a --raw
    ctc erc20 balance 0x956f47f50a910163d8bf957cf5846d573e7f87ca 0x9928e4046d7c6513326ccea028cd3e7a91c7590a --block 
14000000

arguments:
    ERC20_ADDRESS     address of ERC20 token
    WALLET_ADDRESS    address of wallet
    --block BLOCK     block number
    --raw             whether to normalize balance by ERC20 decimals