Improve handling ox extremely large tasks - split them recursively.
Remove roi from TaskSplitter, it is not needed anymore.
Do not pass task split parameter when it is not needed.
closes #196.
Keep only one best result for subtasks.
closes #198.
Store only one result per facet (we dont have more of them because of GPU based result reduction).
closes #197.
Output to Logger.trace().
Remove unneeded import.
Add default task split parameter.