Pull Request for Issue713 attempt2: REIXS Improve XES image processing

This optimizes the REIXSImageInterpolationAB.  It also acts as a clean up to make the code readable and easier to understand.  In terms of performance metrics, the old code used to run at 67-73 ms and the new code runs at 17-32 ms.  Averages being 71ms for the old and 28ms for the new.