Ignore directories for replace_files

app/replace_files.py

@@ -87,6 +87,8 @@ def main():
 
     for new_fname in os.listdir(source_dir):
         new_path = os.path.join(source_dir, new_fname)
+        if not os.path.isfile(new_path):
+            continue
         new_tags = get_tags(new_path)
         new_title = new_tags['title']
         new_artist = new_tags['artist']