* Move the forum box colors into dedicated styles that are easier to
override for the new theme colors.
* Updated the themes so forums and comment thread background cards now
match your chosen style.
* Add yellow and orange theme variants.
* Dark theme fixes to brighten notification colors on mobile
* Add change log buttons around various pages to easily look into the history
of an object in the database:
* User profile page ('about user' and user table history links)
* User friends page
* User/Site gallery page (history of all (user) photos)
* Admin insights page (comments, threads, and blocklist history)
* Admin certification page (history of a user's cert photos)
* Comment history buttons on forums and photos
