Separate files for checking if downloaded previously

[Liz-chan]

Hi, I think a nice improvement would be if PD wrote the files that it downloaded to a separate file, maybe something like downloaded.txt and then it would reference that instead of looking through the current folder.

Right now with the current method, if you move the downloaded profiles away to another drive or to the cloud, PD will just re-download the entire profile if you use it again, therefore a separate file would be really helpful since it would take up barely any space unlike the entire profile folder.