Bye-bye to old database upgrade files and hellow to upgrade.php!

First order of business:  drop all the extraneous user_xxx tables.

lib/db/postgres7.php

@@ -1,19 +1,8 @@
 <?PHP  //$Id$
+// THIS FILE IS DEPRECATED!  PLEASE DO NOT MAKE CHANGES TO IT!
 //
-// This file keeps track of upgrades to Moodle.
-// 
-// Sometimes, changes between versions involve 
-// alterations to database structures and other 
-// major things that may break installations.  
-//
-// The upgrade function in this file will attempt
-// to perform all the necessary actions to upgrade
-// your older installtion to the current version.
-//
-// If there's something it cannot do itself, it 
-// will tell you what you need to do.
-//
-// Versions are defined by /version.php
+// IT IS USED ONLY FOR UPGRADES FROM BEFORE MOODLE 1.7, ALL 
+// LATER CHANGES SHOULD USE upgrade.php IN THIS DIRECTORY.
 //
 // This file is tailored to PostgreSQL 7
 
@@ -1960,6 +1949,8 @@ function main_upgrade($oldversion=0) {
             table_column('log_display', 'field', 'field', 'varchar', '200', '', '', 'not null', '');
     }
 
+    //////  DO NOT ADD NEW THINGS HERE!!  USE upgrade.php and the lib/ddllib.php functions.
+
     return $result;
 }