Group thumbs by tag (only show each thumb once)

[will-moore]

This implements the new Tag sorting layout in the Thumbnail Figure script (see ome/openmicroscopy#1002) and should be tested as part of that PR.

Also confirm that the script still works in Insight, when choosing the same tags in the same order as web.

[pwalczysko]

The script produces what is expected.
Tried to emulate Will's idea with the tags (drug1 - 3, inside each drug category a subcategory OK, strange, dead).
Gave the results in Insight and Web.

RFE: Discussed with Will the need to reformat the output (= the resulting .jpeg), he will probably do it in a different PR.

RFE: Call the resulting .jpg the same way in both clients (now Insight = user-10, i.e. the name of the dataset, Web = Thumbnail figure, i.e. the name of the script - see screenshots)

RFE: Make some description of the expected usage, because there are some strong assumptions made:
- user will understand that the order of tags is crucial for the right result
- user will understand how to put the tags in the right order
I do not think this is self understanding now - I needed a short lecture from @will-moore to get the whole idea. Although we should strive for the features to be self-understanding, a short description seems to me very useful (do not force user to read it of course).

RFE: In Insight, unlike in Web, there is no Preview - as you are choosing your tags for ordering, you have no idea about what the result will be until you really execute the script. This would be quite crucial for the self-understanding feature which is attempted here though.

[jburel]

@will-moore, @pwalczysko, @scottlittlewood: probably better to hold off until after 4.4.7 release
No point to introduce a new divergence.

[will-moore]

@jburel This PR is part of the UI changes in ome/openmicroscopy#1002. I'd really like to avoid pushing this till after the next release, since this causes a lot more work for everyone. We did the same for the split-view-figure and the 4.4.6 release. It means a whole load of rebasing later, opening 2 more PRs, re-testing everything etc. I would argue that this PR (and 1002) actually reduce the divergence between the clients, since without it, you can't run the Thumbnail Figure in the web. The difference between the 2 UIs is small compared to not having the functionality at-all in the web. For the script PR itself, this obviously doesn't introduce any divergence in the clients.

[jburel]

@will-moore: Of course the 2 PR go hand in hand.We just need to be careful before merging anything.
It is not only the divergence at the code level, we have the doc and the scenario out of synch.

[will-moore]

The webclient docs have never been "in sync" with the webclient (never covered all the features), so I don't think that's a good reason to hold off on the feature.
When is the 4.4.7 release currently planned for?

[pwalczysko]

Works as expected. See comments at ome/openmicroscopy#1002.

[atarkowska]

works for me. ready to push