DATAES-472 - Updated changelog.

Author: odrotbohm

src/main/resources/changelog.txt

@@ -1,6 +1,11 @@
 Spring Data Elasticsearch Changelog
 ===================================
 
+Changes in version 3.1.0.RC2 (2018-08-20)
+-----------------------------------------
+* DATAES-472 - Release 3.1 RC2 (Lovelace).
+
+
 Changes in version 2.1.14.RELEASE (2018-07-27)
 ----------------------------------------------
 * DATAES-463 - Release 2.1.14 (Ingalls SR14).