Favorites listing + Notice tweak + Remove ad space

Partial update for the main branch:
* Added a link to Danbooru's favorite listing.
* Altered the way the script uses Danbooru's notice alert so that it doesn't overwrite existing messages from Danbooru.
* Added another style rule that works with hiding advertisements by freeing up the space where the ad usually is.
* Moved the style sheet function to the top to allow it to run first since there's a good chance it'll tie in with more stuff.