option for new tag

www/index.html

@@ -219,6 +219,7 @@
                   <td>
                     <select class="custom-select autodoc_tag_list">
                       <option>Choose tag to edit</option>
+                      <option>New tag...</option>
                     </select>
                     <input type="hidden" class="autodoc_tag_id" value="">
                     <input type="text" placeholder="Tag name" class="autodoc_tag_text d-none">