Improve Arr class documentation.

system/arr.php

@@ -6,7 +6,16 @@ class Arr {
 	 * Get an item from an array.
 	 *
 	 * If the specified key is null, the entire array will be returned. The array may
-	 * also be accessed using JavaScript "dot" style notation.
+	 * also be accessed using JavaScript "dot" style notation. Retrieving items nested
+	 * in multiple arrays is also supported.
+	 *
+	 * <code>
+	 * // Returns "taylor"
+	 * $item = Arr::get(array('name' => 'taylor'), 'name', $default);
+	 *
+	 * // Returns "taylor"
+	 * $item = Arr::get(array('name' => array('is' => 'taylor')), 'name.is');
+	 * </code>
 	 *
 	 * @param  array   $array
 	 * @param  string  $key