works fine with prometheus-client 0.0.18

Igor Živković · Igor Živković · commit 1ce0cebd71bf · 2017-07-06T14:08:23.000+02:00
diff --git a/requirements.txt b/requirements.txt
@@ -1 +1 @@
-prometheus-client==0.0.19
+prometheus-client>=0.0.18
