Allow selections to be async #57
Description
With async.q it would be worthwhile to at least give the option for selections to be able to be async.
Selections like Type (which queries for discourse node type) or discourse:any which queries for discourse relations can take a long time and hang for large graphs.
Ideally, we get the original results and display them to the user, then fire the selection queries ... but this would introduce a few more challenges like handling sorting/filter, navigating away, editing the query, etc.
So initially if we just make selections not block the UI, that would be sufficient.