Akaze: Check on a large dataset that the boundary check is not necessary

[stephanemagnenat]

This is a follow-up of #63, in which an out-of-bound check was added (86b70fe), but looks now to be not necessary after the algorithm was fixed to match the original C++ code (822a3c1).

@vadixidav this issue tracks the validation that the boundary check is not necessary any more, as you wanted to run Akaze a large dataset of yours to make sure of that.