New functions to allow parsing row by row from multiple sources:
cp.setRowParserFinishedCallback(func_returning_bool);
// only one of these should be used at once:
cp.setFeedRowParserCallback(func_returning_char);
cp.setFeedRowParserStrCallback(func_returning_char_pointer);
// I added "Str" version because it is faster in practice when a whole string is supplied
// rather than single character. Non arduino adaptations allowing to test the code on a normal computer.