Change of image properties does not trigger "changes" in ImagePlus

[kephale]

I'm not sure if this is by design or not, but it might be reasonable for changes in metadata to trigger the "changes" flag of an ImagePlus. Perhaps this goes away in IJ2, but it should be an easy modification nonetheless. The specific use case that brought this to mind was making changes to the calibration data of some images and not getting a "Save changes?" dialog after closing a modified image.

[rimadoma]

@kephale Could these be related? https://github.com/scijava/scijava-common/issues/240

[kephale]

Perhaps, I'm not terribly familiar with the IJ1<->IJ2 interface. However, I think the fix just involves adding: myimageplus.changes = true; in a few places, presumably in legacy, but I haven't dug around for the specific methods to modify.

[hadim]

Seems to be related to #140.

By default sync between ImagePlus and ImageDisplay is not enabled. Maybe it explains the bugs we see...