The exu doesn't contain the old scenario entries (Variant_st) but the new
(Exactness_Action).
The recorder doesn't create old rec file but only exu.
The player/inspector support rec files by converting them to the new
format internally.
The structures have been tried to be simpler.
The exu is a EET file for Exactness (Exactness Unit). It currently
contains the scenario and the images shots.
exactness_inspect supports it, as well as the player (only as output).