Feature: Insert or delete slices to/from an Image Geometry. Also replace a slice with data from another slice/image geometry

[imikejackson]

Insert/Delete/Replace slice from an image geometry

The motivation is during a serial sectioning experiment, one slice may have had questionable data acquisition or the data is just know to be bad. A filter to allow a user to perform specific operations on just on that slice would be useful.

• Delete the slice from the image geometry
• Insert another slice into an image geometry
• replace a trouble slice with "default" data
• replace a trouble slice with data from another slice or from another image geometry all together.