Improve aspect ratio filtering for Reddit

[ifl0w]

Maybe we want to modify the UI slightly.
The relevant discussion is here.

[Lucki]

Today Reddit announced major changes to their API so before investing any resources in this issue we should investigate and evaluate what will change and if it's feasible to keep this wallpaper source.

https://old.reddit.com/r/reddit/comments/12qwagm/an_update_regarding_reddits_api/