Added SLIC-zero to SLIC and changed SLIC implementation slightly
Bug fix: removed temporary debug code
Merged the separate loops for SLIC-zero and SLIC into one, and some minor improvements based on feedback on Github.
Some changes based on feedback from discussion on Github.
Added a test for slic_zero and some other changes based on feedback from Github.
Merge pull request #864 from romaniukm/slico-rebase

Add SLIC-zero capabilities to SLIC segmentation.