sendCredits()

Part of the Delta-Algorithm implementation. Shares state information with destination chainId.

Description of arguments of sendCredits():

function sendCredits(
    uint16 _dstChainId,             // destination chainId
    uint256 _srcPoolId,             // source poolId
    uint256 _dstPoolId,             // destination poolId
    address payable _refundAddress  // refund extra native gas to this address
)