As discussed in https://etherpad.wikimedia.org/p/Wikidata_Meeting_Berlin_10262015, we may want to index labels, aliases and descriptions as separate fields in ElasticSearch. This involves the following:
* Separate languages into fallback groups (do not include English)
* For each fallback group, create index field with labels, aliases and descriptions. For labels and descriptions, store them together with language, e.g. for language group `de/de-ch/de-at`, we would have:
```{
labels: [{language:"de", text:"foo}, {language:"de-at", text:"foofoo"}],
aliases: [fuh xyz],
descriptions: [{language:"de", text:"foozy"}, {language:"de-ch", text:"foofoo foo zy"}]
}```
This structure is to enable both searching in these fields in suitable languages for the user and to enable retrieving labels & descriptions from ElasticSearch instead of making extra trip to the SQL database.