Add -s option to use sentence boundaries provided by KorAP tokenizer

Change-Id: Id3aaa50d7775256e336013cc0fbe56803c125052
diff --git a/Changes b/Changes
index 078fb26..5bd0267 100644
--- a/Changes
+++ b/Changes
@@ -1,3 +1,4 @@
+        - -s option added that uses sentence boundaries provided by the KorAP tokenizer (-tk)
 0.03 2021-01-12
         - Update KorAP-Tokenizer to released 2.0 version
         - Improve test suite for recent version