Initialize theme in Admin Plugin (#1069)

* Initialize theme in Admin Plugin

* Updated changelog

CHANGELOG.md

@@ -2,6 +2,7 @@
 ## 04/xx/2017
 
 1. [](#improved)
+    * Initialize theme in Admin Plugin [#1069](https://github.com/getgrav/grav-plugin-admin/pull/1069)
     * Use new system configuration entries for username and password format
     * Reworked Page parent field to use `Pages::getList()` rather than logic in Twig field itself
     * More robust styling of admin themes page [#1067](https://github.com/getgrav/grav-plugin-admin/pull/1067)

classes/themes.php

@@ -14,6 +14,7 @@ class Themes extends \Grav\Common\Themes
         /** @var Themes $themes */
         $themes = $this->grav['themes'];
         $themes->configure();
+        $themes->initTheme();
 
         $this->grav->fireEvent('onAdminThemeInitialized');
     }