## Reorder Pages

Upload documents A, B, C, D with mixed pages.
User must be able to reorder pages (copy/paste pages) so that:

* A will contain pages A1, A2, A3 (in this order)
* B will contain pages B1, B2, B3, B4, B6, B7, B8 (page B5 is missing)
* C will contain pages C1, C2, ..., C8
* D will contain pages D1, D2, D3