Update changelog

Author: Dennis Hoer

CHANGELOG.md

@@ -1,5 +1,13 @@
 # NSSM CHANGELOG
 
+## 4.0.0 2017-08-02
+
+- Convert default recipe to custom resource with idempotence 
+- Allow install of nssm to be optional
+- Properly escape parameters in install action (custom quoting should be removed)
+- Make start service idempotent
+- Unstable version of nssm is used to ensure proper idempotency. Without it, the `load_current_value` would fail to get every setting.
+
 ## 3.0.2 2017-07-13
 
 - Fix whyrun issues