made the api doc better, also replaced SQL with {}. removed additional_columns param on bcms::item::list_items not being used, removed bcms::item::list_pages list_images list_files as they are bcms-ui-wizard specific. change bcms::item::format_string_as_url -url to -string, renamed bcms::item::item_url_duplicate_test to bcms::item::create_unique_url