[geminitrack] Option to patch the links in the gemtext files
Currently, geminitrack never changes the gemtext files (and it's documented) which may break the links if:
- the link is to a directory
foo/bar/
while geminitrack saves the resource asfoo/bar/index.gmi
- or the link is to a name which will not be used for saving, for instance a query
foo.gmi?bar
where the question mark will be replaced with an underscore.
It is currently documented, but it would be cool to have an option to patch the links before saving. Not obvious to integrate in the current code where files are just list of bytes.