[issue1173] Fix parameter order for MergeAndShrinkAlgorithm.

We passed the options for the merge_and_shrink evaluator into
the constructor of an internal class in the wrong order, leading to
wrong behaviour. For example, the boolean option prune_unreachable_states
was interpreted as max_states, so that max_states was set to 0
or 1 based on the boolean flag. This is now fixed.

src/search/merge_and_shrink/merge_and_shrink_heuristic.cc

@@ -32,9 +32,9 @@ MergeAndShrinkHeuristic::MergeAndShrinkHeuristic(
     : Heuristic(transform, cache_estimates, description, verbosity) {
     log << "Initializing merge-and-shrink heuristic..." << endl;
     MergeAndShrinkAlgorithm algorithm(
-        merge_strategy, shrink_strategy, label_reduction, max_states,
-        max_states_before_merge, threshold_before_merge,
+        merge_strategy, shrink_strategy, label_reduction,
         prune_unreachable_states, prune_irrelevant_states,
+        max_states, max_states_before_merge, threshold_before_merge,
         main_loop_max_time, verbosity);
     FactoredTransitionSystem fts = algorithm.build_factored_transition_system(task_proxy);
     extract_factors(fts);