Case sensitive match

[RuedigerVoigt]

This code in parser.py:

        soup = BeautifulSoup(file_content, 'html.parser')
        for link in soup.find_all('a'):

does not match if code falsely uses upper case <A HREF='https://www.example.com/'>.. - like for example the export function from the Chrome bookmark manager.

The simple solution would be to convert everything to lowercase.
This would also mean faster matching.
Yet it looks wrong in the report.