Update ordering of Items when adding them to activity.

Alphabetically ordering makes here more sense.

admin/mappings.php

@@ -49,7 +49,7 @@ $allItems = $pdo->query("
     SELECT i.itemID, i.itemName, ig.groupName
     FROM items i
     JOIN item_groups ig ON ig.groupID = i.groupID
-    ORDER BY ig.sortOrder, i.sortOrder, i.itemID
+    ORDER BY ig.sortOrder, i.itemName, i.itemID
 ")->fetchAll();
 
 // Selected activity filter