add customMenuHTML

WiFiManager.cpp

@@ -1383,6 +1383,10 @@ String WiFiManager::getMenuOut(){
 
   for(auto menuId :_menuIds ){
     if((String)_menutokens[menuId] == "param" && _paramsCount == 0) continue; // no params set, omit params from menu, @todo this may be undesired by someone, use only menu to force?
+    if((String)_menutokens[menuId] == "custom" && _customMenuHTML!=NULL){
+      page += _customMenuHTML;
+      continue;
+    }
     page += HTTP_PORTAL_MENU[menuId];
   }
 
@@ -2733,12 +2737,22 @@ void WiFiManager::setPreOtaUpdateCallback( std::function<void()> func ) {
 
 /**
  * set custom head html
- * custom element will be added to head, eg. new style tag etc.
+ * custom element will be added to head, eg. new meta,style,script tag etc.
  * @access public
  * @param char element
  */
-void WiFiManager::setCustomHeadElement(const char* element) {
-  _customHeadElement = element;
+void WiFiManager::setCustomHeadElement(const char* html) {
+  _customHeadElement = html;
+}
+
+/**
+ * set custom menu html
+ * custom element will be added to menu under custom menu item.
+ * @access public
+ * @param char element
+ */
+void WiFiManager::setCustomMenuHTML(const char* html) {
+  _customMenuHTML = html;
 }
 
 /**