Be careful to use fdupes when packaging plasma-workspace 6

[Fusion Future]

Dear distros: The default image wallpaper plugin shares the same code 
with the slideshow plugin, but KPackage will refuse to load the image 
wallpaper plugin if the ui file is not in the same directory as the 
metadata file. ``` kf.package: Path traversal attempt detected: 
"/usr/share/plasma/wallpapers/org.kde.slideshow/contents/config/main.xml" 
is not inside "/usr/share/plasma/wallpapers/org.kde.image/"
```