add wrapper for new functions due to compability on older wp

includes/help/start.php

@@ -37,7 +37,7 @@
  * @uses    wp add_filter()
  */
 function semr_admin_notice(){
-    if(!strstr($_GET['page'], "semmelstatzR")) return;
+    if(!function_exists("get_user_meta") || !strstr($_GET['page'], "semmelstatzR")) return;
     global $current_user ;
     $user_id = $current_user->ID;
     if(get_user_meta($user_id, 'semr_ignore_notice')) return;
@@ -130,4 +130,4 @@ function semmelstatzR_help($contextual_help, $screen_id, $screen) {
     return $semrContextHelp.$contextual_help;
 }
 add_filter('contextual_help', 'semmelstatzR_help', 10, 3);
-?>
+?>

semmelstatzR_startup.php

@@ -84,4 +84,11 @@ if(class_exists("Upgrademe")) {
         return 'http://www.php-backoffice.de/updates/test/semr_update.php';
     }
 }
-?>
+
+// function wrappers for older wp versions
+if(!function_exists("plugin_dir_path")) {
+    function plugin_dir_path($file) {
+        return trailingslashit(dirname($file));
+    }
+}
+?>