Added what I expect the length of those two dendrograms to be.
Added a test that indicates I don't compute wraparound centers right.
Revert "I forgot that the last index is one less than .shape -- fixed that!"

This reverts commit a06578be4af37ff2f45ba2600894a4cfc064a366.

I realized that, from a pixel-math basis, this change was 100% wrong.
Tentative fix to work around WCS stubbornness at edge. Possibly will revert.