Fix namespace missing backslash / wrong class

Plugin.php

@@ -2,14 +2,14 @@
 
 namespace Plugin\Theme;
 
-use Core\PluginBase;
+use Core\Plugin\Base;
 
-class Plugin extends PluginBase
+class Plugin extends Base
 {
  public function initialize()
  {
  $this->template->hook->attach('template:layout:head', 'theme:layout/head');
  $this->template->hook->attach('template:layout:top', 'theme:layout/top');
- $this->template->setTemplateOverride('template:header', 'theme:layout/header');
+ $this->template->setTemplateOverride('header', 'theme:layout/header');
  }
 }