Empty grouping labels should provide a fallback

[kimisgold]

I was testing to see what would happen if I left a number of the label fields empty, and the result is that a grouping can appear with a blank title in both the Hierarchy block and the main heading in the public view. I would expect the fallback to be the item set name, or "[Untitled]".

Here's the setup within Hierarchy.

Here's the grouping with an empty title.

Here's the empty title in the public view.

(#1)

[matthewjmckinley]

You're right, that could be more elegant. A Hierarchy can't really fall back on an item set, since those are assigned at the Grouping level under the Hierarchy, but I can have them show as [untitled] when nothing is there.

[matthewjmckinley]

Fixed in https://github.com/omeka-s-modules/Hierarchy/commit/aa552652f4d468c2eb42f8c1273a5c705eb974fd