Completed (de)serialization of RoiSet

See merge request !18

Exporting patch masks does not automatically make a PatchStack, which forces them to all be the same size

By default, return non-expanded patches and masks; allow contour and mask overlays in non-expanded patches

Standardize patch (mask) getters return ad-hoc DataFrames, and _acc methods wrap these in PatchStack accessors (which automatically become shape of largest patch)

Broadcasting is work except in some cases that appear to coincide with truncation of ROI in patch bounds

Removed solidity from features, this was no longer being used and was triggering convex hull warnings

Implementing alternative dataframe generation where z-positions are in object map, i.e. do not need to be de-projected from raw

Implemented and tested object identity labeling in 3D with and without connectivity between z-frames

Changes supporting AutoMic integration

See merge request !15

This reverts commit 49581d11.