Support cursor pagination in paginate

Needed for backend#503 (closed)

Requires !196 (merged)

With this pagination, you won't have page nor count keys, only next & previous cursor keys.

The ResponsePaginator class should make the initial query without the page argument (for all paginations), in order to then detect if it's a PageNumberPagination or a CursorPagination.

The retries system should be generic, and store the cursor instead of the page number.

We'll lose some logging information as we can't show the progress.