LPS-32362 Add Folder facet to search

The facet only handles a single term (in this case, folderId). There is no way to get the folder name without knowing its className (DLFolder, JournalFolder, BookmarksFolder).

@JorgeFerrer and I thought of a solution based on indexing the folders and retrieving them with a searcher just by folderId. The name for each term of the facet is then obtained from the indexed document. 

The indexation of JournalFolder and BookmarksFolder follow the same pattern as for DLFolder. Notice that JournalFolder does not support trash, yet, so there is no status logic.