Merge pull request #231 from asherf/tox

Update changlog.

Author: asherf

CHANGELOG.md

@@ -4,6 +4,7 @@
 
 * Remove support for older django and python versions
 * Add support for Django 3.0
+* Add support for [PostGIS](https://github.com/korfuri/django-prometheus/pull/221), Thanks [@EverWinter23](https://github.com/EverWinter23)
 
 ## v2.0.0 - Jan 20, 2020