treefmt unfortunately doesn't a way to detect scripts with no file
extensions unless you entered the filename manually. We'll have to
rename them with the file extension for the time being.
It's certainly better and more flexible for other formats. Except I'm
still not going to cater much for odder Thunderbird feed folder
structures. This is mainly for myself anyways. I'll just avoid setting
it up like that. :)
Not much respect for `category` attribute, apparently. I'll update it at
some point to consider the usual folder structure instead.
For now, it's not a problem for me since the exported feeds to be used
are so low anyways.
