Carbonate the refutation game functions

The functions update_game, timeout and apply_outcome in Sc_rollup_storage are currently not carbonated. Since they will be called by application of the manager operations Sc_rollup_refute and Sc_rollup_timeout they should be carbonated---this issue is to add appropriate gas constants and benchmarks for those.

Apparently, the refutation game storage functions already are carbonated (they are mainly calls to Storage functions which are already carbonated). The main thing that would need to be carbonated is the proof verification which will probably occur in Sc_rollup_game_repr.play which needs to be carbonated and then change the scope of the mr: "carbonate the refutation game storage functions" <- "carbonate the refutation game functions".

By transitivity, we also need to carbonate the functions of the PVM used during refutation games. (This implies changing the interface of the PVM.)