Enable levels 4 and 5

src/levels/mod.rs

@@ -88,5 +88,7 @@ pub fn registry() -> Vec<Box<dyn Level>> {
         Box::new(l01_minimum::Minimum),
         Box::new(l02_kv::KeyValue),
         Box::new(l03_dict::Dict),
+        Box::new(l04_list::List),
+        Box::new(l05_dict_list::DictList),
     ]
 }