Clean leading dots from remote downloaded files

[DiegoPino]

What?

There is an open pull to deal with composting files that start with one or two dots (workaround/a setting) but it seems a bad practice to fetch these and store them because a dot as prefix means hidden file anyways.

Given that Filenames are really a hint for purists in Archipelago I feel confident this won't make anyone angry. If someone is angry after this we can revisit the decisions

[DiegoPino]

Ok we do this. But also use proper file names folks!