R1:89d038f53e8e

Make Portals indexable with Ferret

Summary:
Ref T13275. Add portals to the search index so that:

- they show up in fulltext global search; and
- the typeahead actually uses an index.

Also make them taggable with projects as an organizational aid.

Test Plan: Indexed portals with `bin/serach index`, searched for a portal with "Query", with fulltext search in main menu, with typehead on "Install Dashboard...", changed the name of a portal and searched again to check that the index updates properly.