Rearrange Slices Operator

[william-silversmith]

For alignments, it's pretty useful to be able to take a raw stack and fix transpositions and shifts and "fake" blanks in the z stack. This would take a JSON dict or list that contains a mapping of index to index. The mapping must be injective.

This could be done either in-place (with one or more temp slice copies) or as a full copy.