core simplifications, especially detector iterators

added 6 commits

• f0e19019 - ScatteringSimulation::simCoordSystem simplify
• 5a0d088a - IDetector: rm ROI iterator
• 0fe97f7d - SimulationAreaIterator: rm mode
• 82816823 - ScatteringSimulation::packResult use m_detector->iterateOverNonMaskedPoints
• 554be94c - IDetector rm begin/endNonMaskedPoints
• c3f625c0 - rm IDetector::detectorIndexToRegionOfInterestIndex

Compare with previous version

enabled an automatic merge when the pipeline for c3f625c0 succeeds

merged

mentioned in commit 6e8d8d64