Update CHANGELOG

Author: Aaron Baer

CHANGELOG.md

@@ -4,6 +4,8 @@ This project adheres to [Semantic Versioning](http://semver.org/).
 This CHANGELOG follows the format listed at [Keep A Changelog](http://keepachangelog.com/)
 
 ## [Unreleased]
+- Correctly evaluate and collect metrics for active connections and active connections waiting on backend locks
+- Add new metric `total`
 
 ## [0.1.0] - 2016-03-09
 ### Added