1) They must all start with "admin_". This pattern is not directly
routable.
2) Their urls must be /admin/xxx.
3) The Admin_Controller will take the xxx and look for Admin_Xxx_Controller
and will delegate to that admin controller, after doing security checks.
Moved the users and dashboard views into individual modules for now.
o Copy all the assets from default to default_admin so that they're
totally separate
o Get rid of $item_theme
o Rename list_users.html.php to users.html.php
o use __call in admin controller to allow us to load any admin page
