PR: https://github.com/aibasel/downward/pull/319

I can confirm that the current behaviour is a bug. I didn't check thoroughly how this information gets propagated through the sub-searches, but in any case the correct behaviour here would be for

`iterated([astar(blind(), max_time=0)])`

to result in similar output and the same search exit code as

`astar(blind(), max_time=0)`

If the new code achieves this, feel free to merge.

Configuration `iterated([astar(blind(), max_time=0)])` reports `Task is provably unsolvable.` on blocks/probBLOCK-4-0.pddl


This bug was introduced by issue1201.
The method `get_finished_search_status` missed the case where the search could have a timeout.
In that case it could still be a search that is complete_within_bound and unbounded but this is not sufficient to report the finished_search_status of UNSOLVABLE.

The finished search status should be TIMEOUT.

PR: https://github.com/aibasel/downward/pull/319