only read menus that exist (instead of cryptically failing)

index.php

@@ -148,11 +148,13 @@ for ($i=1;$i<=count($url_ex);$i++) {
 $f3->set('url', $url);
 $f3->set('is_home', in_array($url[0],["/","/home"]));
 $f3->set('level', 1); // this is for templates, to be abl to count nesting
-read_menu("main");
-read_menu("footer");
-#read_menu("network");
-read_menu("languages");
-read_menu("mobilelang");
+
+if (is_array($f3->get('nav'))) {
+    foreach ($f3->get('nav') as $k=>$v) {
+        read_menu($k);
+    }
+}
+