add changelog for #1243

Author: Tobion

CHANGELOG.md

@@ -14,7 +14,8 @@ All notable changes to this project will be documented in this file based on the
 
 ### Improvements
 
-- added support for the "explain" flag of AnalyzeAPI [PR-1254](https://github.com/ruflin/Elastica/pull/1254)
+- added support for the "explain" flag of AnalyzeAPI [#1254](https://github.com/ruflin/Elastica/pull/1254)
+- added support for the "request_cache" search option [#1243](https://github.com/ruflin/Elastica/pull/1243)
 
 ### Deprecated