Add changelog

Author: asherf

CHANGELOG.md

@@ -0,0 +1,17 @@
+# Changelog
+
+## v2.0.0 - Jan 20, 2020
+
+* Added support for newer Django and Python versions
+* Added an extensibility that applications to add their own labels to middleware (request/response) metrics
+* Allow overriding and setting custom bucket values for request/response latency histogram metric
+* Internal improvements:
+  * use tox
+  * Use pytest
+  * use Black
+  * Automate pre-releases on every commit ot master
+  * Fix flaky tests.
+
+## v1.1.0 -  Sep 28, 2019
+
+* maintenance release that updates this library to support recent and supported version of python & Django