Add a deprecation note for a path which has been long deprecated.
@@ -4,6 +4,14 @@ Changelog
in development
--------------
+Changed
+~~~~~~~
+
+* ``st2actions.runners.pythonrunner.Action`` class path for base Python runner actions has been
+ deprecated since StackStorm v1.6.0 and will be fully removed in StackStorm v2.7.0. If you have
+ any actions still using this path you are encouraged to update them to use
+ ``st2common.runners.base_action.Action`` path.
+
2.5.0 - October 25, 2017
------------------------
