This patch changes the default algorithm used by the olio.triangulation.reorient() function to be the numpy linear algebra svd function. The alternative fast approximate algorithm has been found to fail badly for surfaces with a normal vector direction close to (1.0, 1.0, 0.0). (The fast approximate mode was designed primarily for working with horizon surfaces at modest dips, for which it remains suitable.)
The change will increase computation time when reorienting surfaces with large numbers of points. The intention is to re-engineer a better fast approximate algorithm which will become the default when operational.