Previously, media queries weren't keep when downloading styles from ref
tags.
It have been fixed so that media attribute are kept when creating style
tags from ref tags.
Previously, self_html_function was a function taking all parameters as
arguments.
As new optionnal parameters are beeing added, the function had too much
arguments and each usage of the function would have to be modified each
time an argument will be added.
Therefore, it have been moved to a configuration structure with a `run`
function taking only one argument, the html string.
Previously, when the image url contained data, it tried to parse an url
and failed, instead of keeping data.
It have been fixed so that images where url is starting by 'data' are
not modified.
Add retrieval from le monde diplomatique
Previously, 404 pages were injected in the document when downloading
styles
Now, the downloader returns None when documents are not found
