Added opt() method to QueryBuilder

Change-Id: I9033fc0b8d1a5c0ebac4468d66c8e381d8c3fbb3
diff --git a/Changes b/Changes
index aa15d42..4bc1f21 100644
--- a/Changes
+++ b/Changes
@@ -13,6 +13,7 @@
       korap.index.TestNextIndex.testNextExpansionBug() (margaretha)  
     - [bugfix] Fixed left expansion match order (margaretha)
     - [bugfix] Fixed right expansion match order & expansion over start (margaretha)
+    - [feature] Added opt() method to QueryBuilder (diewald)
 
 0.58.0 2018-09-03
     - [feature] Implemented referencing cached collection (margaretha)