Pass Image_ID from selected image in OMERO.web

[ctrueden]

The currently selected image in OMERO.web is supposed to be automatically populated as the script's Image_ID if that field exists. But for some reason it isn't. This means you have to manually type the image ID when running ImageJ commands through OMERO.web, which is too bad. Figure out what the problem is.

[ctrueden]

The issue is that the field on the OMERO side needs to be called Image_IDs (IIRC), not Image_ID, and it needs to be a list, not a single long. That way, scripts can support a list of images for situations such as multiple thumbnails selected in OMERO.web.

The tricky part is that handling multiple selected images across the ImageJ boundary is non-trivial. Suppose you have a common ImageJ command that operates on an input image. Just one, not multiple. This is the typical scenario. Now in OMERO.web, you select three images and say "Find Edges"!

• As a first cut fix for this bug, we could pass that list of Image IDs as the value of the Image_IDs parameter, which then gets culled to the first image ID which gets passed over the wire to ImageJ, and then Find Edges works... but only on the first selected image. Not all three.
• But better would be for the ImageJ script runner to be smarter, and realize that its Image_IDs parameter maps to a single image, so we must sequentially execute Find Edges on each ID in the list, returning the results as an output list of processed images. Making this work as expected is more involved, and perhaps should be filed as a separate issue for a later milestone.

[ctrueden]

Very related (duplicate-ish, actually) to #29.