Cursor-based pagination to fetch the "previous" page

[VojtechVitek]

Is it possible to use the cursor-based pagination to fetch the previous page (ie. to get all the new items with higher score than items coming from the first request)?

I guess to "go back", we'd have to use reversed order of the Redis data (ZRANGEBYSCORE, max=+inf, min=StartScoreStr) at

roshi/cluster/cluster.go

Line 557 in 4c3eb77

"ZREVRANGEBYSCORE",

Would it make sense? Does Roshi already support this feature (and I'm just blind)?

Any feedback appreciated.

Related to #36, CC: @peterbourgon @pkieltyka

[peterbourgon]

It's technically possible, and you've identified the right place for the changes, but it's not currently supported. I can't see any reason why it couldn't be, but it's not a use-case SoundCloud currently has, so I suspect the best path forward would be to create a PR, which I'd be happy to review.