Update changelog

Author: brianc

CHANGELOG.md

@@ -4,6 +4,12 @@ For richer information consult the commit log on github with referenced pull req
 
 We do not include break-fix version release in this file.
 
+### 7.1.0
+
+#### Enhancements
+
+- [You can now supply both a connection string and additional config options to clients.](https://github.com/brianc/node-postgres/pull/1363)
+
 ### 7.0.0
 
 #### Breaking Changes