COURSE DISPLAY REVAMP

OK, some big changes here to the front end, particularly in
course categories and course display.

Course categories can now be nested (to any level).

Courses and course categories can now be manually sorted
any way required.

There is a groovy front end for managing these, and a better
range of options for formatting the front page.

It all still needs some polishing, which I'll be doing over
the next couple of days, including better auto-sorting.

I would not use this on production systems just yet.

lib/db/postgres7.sql

@@ -31,6 +31,12 @@ CREATE TABLE prefix_course (
 CREATE TABLE prefix_course_categories (
    id SERIAL PRIMARY KEY,
    name varchar(255) NOT NULL default ''
+   description text NOT NULL default '',
+   parent integer NOT NULL default '0',
+   sortorder integer NOT NULL default '0',
+   courseorder text NOT NULL default '',
+   visible integer NOT NULL default '1',
+   timemodified` integer NOT NULL default '0'
 );
 
 CREATE TABLE prefix_course_display (