feed es view (bug 1036216)

Breaking https://github.com/mozilla/zamboni/pull/2298 up.

- Do a filter on FeedItem by region that puts matching region/carrier operator shelves on top.
- Do an OR query for FeedApp/Brand/Collection/Shelf using IDs
- Do an OR query for apps using IDs

Relies on [indexers](https://github.com/mozilla/zamboni/pull/2314) and [serializers](https://github.com/mozilla/zamboni/pull/2313).
Even if there's no carrier now, in the future we'll be adding more functions that depend on different attributes. Is it worth writing an entirely different query to avoid empty functions?