Use consistent parameter order of (before, after) throughout update APIs

[rmunn]

Currently most of the update APIs use the parameter order (before, after), but there are some that have the order (after, before). Since these parameters are the same type the compiler won't be able to catch it if we accidentally call them with (before, after) and we'll get runtime bugs where an update gets applied in the "wrong direction". We should make the update APIs consistent so that any APIs that take (before, after) or (old, new) parameters always take them in the same order.

[rmunn]

Currently #1267 is still outstanding, so I'd like to wait until it's merged before tackling this. That way we'll minimize the chances of bugs being introduced by merge conflict resolutions.

[rmunn]

Going to start working on this using #1295's branch as a base, then rebase to develop when #1295 is merged.