Improve Memory Tagging

[ritzdorf]

Memory tagging needs to be improved for certain opcodes including ReturnDataCopy and CallDataCopy.

Reference: https://github.com/eth-sri/securify/blob/master/src/main/java/ch/securify/analysis/AbstractDataflow.java#L472

Example:

No MissingInputValidation here:

contract SimpleBank {
    bytes32 x;
    function withdraw(bytes  memory a) public {
        x = keccak256(a);
    }
}

but it is detected if a non-dynamic data type is used.