Stefano Cerri

Results 2 issues of Stefano Cerri

- Speed up of approx 1.5x/2x for cross-sectional, approx 1.2x for longitudinal - Final segmentation(s) might change for some voxels due to different optimization scheme

Fix `"ValueError: Buffer dtype mismatch, expected 'int_t' but got 'long long'"` error on Windows (found when building samseg on Windows). Most probably fix #3 (not tested)