Added note of where the script is to regenerate the file, and who is meant to run it.

Author: Danack

scripts/gen-phpdoc-tz-list.php

@@ -36,6 +36,10 @@
 <!-- $Revision$ -->
 <!-- AUTO GENERATED, DO NOT TRANSLATE OR MODIFY BY HAND -->
 
+<!-- The script to generate this file is scripts/gen-phpdoc-tz-list.php -->
+<!-- in the doc-base repo. However, it should only need to be run when  -->
+<!-- the tzdb file is updated by the maintainer of DateTime/timelib.    -->
+
 <appendix xml:id="timezones" xmlns="http://docbook.org/ns/docbook" xmlns:xlink="http://www.w3.org/1999/xlink">
  &date.timezone.intro.title;
  &date.timezone.intro;