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

record entry returned by object class map export is no longer a dictionary of paths, but rather one path for object map

Now that RoiSet is in base, remove dependency on ilastik in its test; tests now open segmentation mask from file

Progress on testing classify_by method; need to pass preference of channel to patch generator without disrupting existing options to export RGB / multichannel stacks

Product methods call RoiSet directly; this is causing problems with multichannel ones where raw data is essentially re-issues to RGB channels