add aluminum information and fix minor bugs

src/materials.py

@@ -211,7 +211,7 @@ def main():
     print(args)
 
   if args.command == 'list':
-    file_list = read_dir(absolute_path("data"), "INFO.json", True)
+    file_list = read_dir(absolute_path("data"), ["INFO.json", "example.json"], True)
     for filename in file_list:
       file, _ = os.path.splitext(os.path.basename(filename))
       print(file)
@@ -244,6 +244,7 @@ def main():
       print_dict(data_dict)
 
     else:
+      data = load_material(args.materialname)
       print_material(data)
 
   return 0