Empty folders readme (#366)

Author: ryanmitchell

README.md

@@ -33,7 +33,13 @@ If you originally opt-out of importing existing content, then later change your
 - Taxonomies: `php please eloquent:import-taxonomies`
 - Sites: `php please eloquent:import-sites`
 
-### Syncing Assets
+### Assets
+
+#### Empty Folders
+
+If your assets are being driven by the Eloquent driver then the database is used as the source of truth for the folder listing, so if no file is present inside a folder then it will not be shown.
+
+#### Syncing
 
 If your assets are being driven by the Eloquent Driver and you're managing your assets outside of Statamic (eg. directly in the filesystem), you should run the `php please eloquent:sync-assets` command to add any missing files to the database, and remove files that no longer exist on the filesystem.