Changes throughout Moodle to remove any reserved words from the

Moodle tables.

ie user -> userid in many tables, plus in user_students
   start -> starttime and end -> endtime

I've just done all this as carefully as I could ... I don't think
I missed anything but it's pretty intensive work and I'd be fooling myself
if I didn't think I'd missed a couple.

Note that this version should pretty much be able to bootstrap itself
using PostgreSQL now ... but this is untested

lib/db/postgres7.sql

@@ -54,7 +54,7 @@ CREATE TABLE course_sections (
 CREATE TABLE log (
    id SERIAL PRIMARY KEY,
    time integer NOT NULL default '0',
-   "user" integer NOT NULL default '0',
+   userid integer NOT NULL default '0',
    ip varchar(15) NOT NULL default '',
    course integer NOT NULL default '0',
    module varchar(10) NOT NULL default '',
@@ -115,21 +115,21 @@ CREATE TABLE "user" (
 
 CREATE TABLE user_admins (
    id SERIAL PRIMARY KEY,
-   "user" integer NOT NULL default '0'
+   userid integer NOT NULL default '0'
 );
 
 CREATE TABLE user_students (
    id SERIAL PRIMARY KEY,
-   "user" integer NOT NULL default '0',
+   userid integer NOT NULL default '0',
    course integer NOT NULL default '0',
-   "start" integer NOT NULL default '0',
-   "end" integer NOT NULL default '0',
+   timestart integer NOT NULL default '0',
+   timeend integer NOT NULL default '0',
    time integer NOT NULL default '0'
 );
 
 CREATE TABLE user_teachers (
    id SERIAL PRIMARY KEY,
-   "user" integer NOT NULL default '0',
+   userid integer NOT NULL default '0',
    course integer NOT NULL default '0',
    authority integer NOT NULL default '3',
    role varchar(40) NOT NULL default ''