Download gallery from waifubitches.com, ososedki.com
Adds a download button to waifubitches.com and ososedki.com (displayed next to "share on fb" etc. buttons).
Detects images in a gallery, fetches them (or if the image can't be fetched — it's thumbnail) and packs them into a ZIP available for download.
If the fetching is stuck, try refreshing the page.
