updated link to changelog.md

Author: bhuvnesh17

README.md

@@ -314,7 +314,7 @@ Always feel free to fork and contribute any changes directly via [GitHub](https:
 |Controller Compatibility  |3.7 or Later|
 |Product Tested On         |SQLServer 4.1,4.2, Vertica|
 |Last Update               |04/04/2018 |
-|List of Changes           |[Change log](https://github.com/Appdynamics/SQLMonitor/changelog.md) |
+|List of Changes           |[Change log](https://github.com/Appdynamics/SQLMonitor/blob/master/CHANGELOG.md) |