s/delete/free/g

lib/stack.c

@@ -28,12 +28,12 @@ void initialize_stack(struct stack *stack) {
   return;
 }
 
-void delete_stack(struct stack *stack) {
+void free_stack(struct stack *stack) {
   struct stack *tmp_stack;
 
   while (stack) {
     tmp_stack = stack->next;
-    delete_card(stack->card);
+    free_card(stack->card);
     free(stack);
     stack = tmp_stack;
   }