Fix clippy warnings.

src/storage.rs

@@ -8,13 +8,6 @@ pub struct Storage {
 }
 
 impl Storage {
-    pub fn new() -> Self {
-        Storage {
-            keys: HashMap::new(),
-            items: Vec::new(),
-        }
-    }
-
     pub fn contains_key(&self, key: &str) -> bool {
         self.keys.contains_key(key)
     }
@@ -54,3 +47,12 @@ impl Storage {
         self.keys.keys()
     }
 }
+
+impl Default for Storage {
+    fn default() -> Self {
+        Self {
+            keys: HashMap::new(),
+            items: Vec::new(),
+        }
+    }
+}