Add fragment for wallpaper categories.

[dkanada]

I would like to add Paranoid Android and OnePlus wallpapers, they look quite nice.

[conrad-heimbold]

I don't mind :)
As long as you don't take choice options away from the user, but only add those; you don't even have to ask, IMHO.

[dkanada]

Definitely not removing the current ones, they also look nice. I was just adding these issues to remind myself, my summer is becoming very busy.

EDIT: Also, I was thinking of renaming this app since I hate leaving (fork) next to the app name on F-Droid, if you have any ideas let me know. I'm not very good at naming things.