extend suggest with labels for parents

[MortenHofft]

From gbif/hosted-portals#289

In the registry I have to do 42 requests for a single keystroke on e.g. PreservationType
It isn't really something I want to do in a public facing product that should perform well. For that we probably need a backend that supports that kind of functionality.

ping @marcos-lg
Currently I can do https://api.gbif.org/v1/vocabularies/PreservationType/concepts/suggest?q=sto&locale=en-AR

that will return

[
  {
    "key": 1106,
    "name": "StorageOutdoors",
    "labels": []
  },
...
]

getting the label with fallback to english, as well as all the parent labels would make it more usable. Currently I would have to do an extra lookup for each result without a label, and secondly an additional lookup for each parent. And do so for all results. And so we end up with many requests per keystroke

[marcos-lg]

Closed in favor of #140