Explicitly expose array_unique Twig filter

CHANGELOG.md

@@ -9,6 +9,7 @@
     * Fix issue with using Yaml::parse direcly on a filename, now deprecated
     * Fix [#891](https://github.com/getgrav/grav-plugin-admin/issues/891) Add pattern for frontend validation of folder slugs
     * Fix issue with Inflector when translation is disabled [https://github.com/getgrav/grav-plugin-simplesearch/issues/87](https://github.com/getgrav/grav-plugin-simplesearch/issues/87)
+    * Explicitly expose `array_unique` Twig filter
 
 # v1.1.9
 ## 12/13/2016

system/src/Grav/Common/Twig/TwigExtension.php

@@ -87,6 +87,7 @@ class TwigExtension extends \Twig_Extension
             new \Twig_SimpleFilter('truncate', ['\Grav\Common\Utils', 'truncate']),
             new \Twig_SimpleFilter('truncate_html', ['\Grav\Common\Utils', 'truncateHTML']),
             new \Twig_SimpleFilter('json_decode', [$this, 'jsonDecodeFilter']),
+            new \Twig_SimpleFilter('array_unique', 'array_unique'),
         ];
     }