Check whether annotator works for edge patches

[rwood-97]

Describe the bug I think at the moment the annotator assumes all patches are the same size (e.g. if you did square_cuts=True). If you haven't used this arg, this could be a problem for edge patches since they have shapes that are different from the normal patches. Equally, if using square cuts, what happens with overlapping patches?

We should check what happens with these edge patches when trying to build a context image.