add get_str_list() for config

Converts a config value written as a comma-sparated list into
a Python list of strings.

nominatim/clicmd/setup.py

@@ -128,7 +128,7 @@ class SetupAll:
                                                   drop=args.no_updates)
             LOG.warning('Create search index for default country names.')
             country_info.create_country_names(conn, tokenizer,
-                                              args.config.LANGUAGES)
+                                              args.config.get_str_list('LANGUAGES'))
             if args.no_updates:
                 freeze.drop_update_tables(conn)
         tokenizer.finalize_import(args.config)