add cleaning method to normlize doc_numbers
add cleaning method to normlize doc_numbers

yngcan/patentprocessor,funginstitute/patentprocessor,yngcan/patentprocessor,funginstitute/patentprocessor,funginstitute/patentprocessor,nikken1/patentprocessor,yngcan/patentprocessor,nikken1/patentprocessor,nikken1/patentprocessor