updated changelog for 0.52

Changelog.md

@@ -2,6 +2,11 @@
 
 All notable changes to this project will be documented in this file.
 
+## [0.52] - 2020-09-07
+- POL1-228 (and others):
+  - allow /poller/interfaces to be called without an argument
+  - removed /poller/services
+
 ## [0.51] - 2020-08-20
 - POL1-137: add remaining service categories and test vectors