[Enhancement] Show Site Favicon for Hyperlink Blocks

[soupermkc]

Mostly self-explanatory, utilize the destination site's favicon for hyperlink blocks so you can easily tell at a glance what it'd link to without hovering over the block. Could add a 'link' overlay to the block as well to make it more clear that it's a link to a page, and not just a static image.
Likely have the server pull the favicon and not the client, so there aren't any unnecessary connections to external websites on the client's side.