[Request/Windows] Add a function to get Special Folder paths

[vico93]

Basically, add a "wrap" to SHGetKnownFolderPath's Windows API function that would allow us to dynamically get the path of variable folders like My Documents/Documents, Saved Games and others that can be moved around by the computer user.

I didn't see anything similar on the documentation, if something that could achieve this already exists in nativefs, please disregard this idea and take my apologizes.