Added arrayLower() method

CHANGELOG.md

@@ -3,6 +3,7 @@
 
 1. [](#new)
     * Added support for custom `FormFlash` save locations
+    * Added a new `Utils::arrayLower()` method for lowercasing arrays
 1. [](#improved)
     * Use new `Utils::getSupportedPageTypes()` to enforce `html,htm` at the front of the list [#2531](https://github.com/getgrav/grav/issues/2531)  
 1. [](#bugfix)

system/src/Grav/Common/Utils.php

@@ -323,6 +323,17 @@ abstract class Utils
         return (object)array_merge((array)$obj1, (array)$obj2);
     }
 
+    /**
+     * Lowercase an entire array. Useful when combined with `in_array()`
+     *
+     * @param array $a
+     * @return array|false
+     */
+    public static function arrayLower(Array $a)
+    {
+        return array_combine(array_map('strtolower', $a), $a);
+    }
+
     /**
      * Simple function to remove item/s in an array by value
      *