Add releasenote to tag the Patrole for Stein release

This commit adds the releasenote to tag Patrole for Stein
and needed for version 0.5.0 to release.

Change-Id: Ibffc826d207bbc57c0c4336810f91b6e0134330b
diff --git a/releasenotes/notes/patrole-stein-release-874b36f2fedcd2fb.yaml b/releasenotes/notes/patrole-stein-release-874b36f2fedcd2fb.yaml
new file mode 100644
index 0000000..83f066b
--- /dev/null
+++ b/releasenotes/notes/patrole-stein-release-874b36f2fedcd2fb.yaml
@@ -0,0 +1,15 @@
+---
+prelude: >
+    This release is to tag the Patrole for OpenStack Stein release.
+    After this release, Patrole will support below OpenStack Releases:
+
+      * Stein
+      * Rocky
+      * Queens
+      * Pike
+
+    Current development of Patrole is for OpenStack Train development
+    cycle. Every Patrole commit is also tested against master during
+    the Train cycle. However, this does not necessarily mean that using
+    Patrole as of this tag will work against a Train (or future release)
+    cloud.