Fix comment in plugin-registry header

Fix the comment to actually be a comment.  Regenerate page.

Although we've got a pretty cool system for generating this, I wonder
if anyone actually looks at it?  Maybe it's just helpful as a form of
SEO.

Change-Id: I15aaa983716f9ee897293c2954ca7ae561951372
diff --git a/data/devstack-plugins-registry.header b/data/devstack-plugins-registry.header
index 6119ab5..576dbbd 100644
--- a/data/devstack-plugins-registry.header
+++ b/data/devstack-plugins-registry.header
@@ -1,18 +1,16 @@
-..
+.. Note to patch submitters:
 
-  Note to patch submitters:
+   # ============================= #
+   # THIS FILE IS AUTOGENERATED !  #
+   # ============================= #
 
-  # ============================= #
-  # THIS FILE IS AUTOGENERATED !  #
-  # ============================= #
+   ** Plugins are found automatically and added to this list **
 
-  ** Plugins are found automatically and added to this list **
+   This file is created by a periodic proposal job.  You should not
+   edit this file.
 
-  This file is created by a periodic proposal job.  You should not
-  edit this file.
-
-  You should edit the files data/devstack-plugins-registry.footer
-  data/devstack-plugins-registry.header to modify this text.
+   You should edit the files data/devstack-plugins-registry.footer
+   data/devstack-plugins-registry.header to modify this text.
 
 ==========================
  DevStack Plugin Registry