Add Viewport up/down scroll

src/main.rs

@@ -202,7 +202,8 @@ impl AppDelegate<StilettoState> for Delegate {
         if cmd.get(commands::SAVE_FILE_AS).is_some() || cmd.get(commands::SAVE_FILE).is_some() {
             let mut path_buf = cmd.get(commands::SAVE_FILE_AS)
                 .map(|file_info| file_info.path().to_path_buf())
-                .unwrap_or(data.current_file_path.as_ref().cloned().unwrap());
+                .or_else(|| data.current_file_path.as_ref().cloned())
+                .unwrap();
             path_buf.set_extension("stlt");
 
             let res_file = File::create(&path_buf);