修复默认封面没有用CDN函数的问题

views/book/setting.tpl

@@ -171,7 +171,7 @@
             <div class="form-right">
                 <label>
                     <a href="javascript:;" data-toggle="modal" data-target="#upload-logo-panel">
-                        <img src="{{.Model.Cover}}" onerror="this.src='/static/images/book.png'" alt="封面" style="max-width: 120px;border: 1px solid #999" id="headimgurl">
+                        <img src="{{.Model.Cover}}" onerror="this.src='{{cndimg "/static/images/book.png"}}'" alt="封面" style="max-width: 120px;border: 1px solid #999" id="headimgurl">
                     </a>
                 </label>
             </div>