Back button doesn't work for random card viewing

[jkomoros]

View a card in random mode. Randomize a couple of times. Then try to go back, hit the back button. All of the new collections are not in the back buffer (since no URL changed) so you go back to the first collection you viewed on load.

Perhaps add the card you're viewing currently randomly in the URL so it's in the back buffer?

[jkomoros]

Any collection that uses sort/random should automatically put the card-id in the URL. Other collections are stable, which means that if you navigate to e.g. c/bits-and-bobs/ then the first card will be the same each time, so there's no need to remember the specific card in the URL.

But every time the random seed is updated, if sort/random is in the active collection, the card changes.

Although note that if you had c/everything/limit/1/sort/random/some-old-id and some-old-id is filtered out of the collection due to the old seed, it would also not show up. You'd need something that special cases sort/random to ignore limit/n or something. Hmmm...