uac.pm: add admin permission

admin permission is no more dependent on the name
of the role, but can be assigned to any role.
Users assigned to admin role have all permissions.

install/migrate.sql

@@ -300,3 +300,7 @@ CREATE TABLE `calcms_help_texts` (
   PRIMARY KEY (`id`));
 
 ALTER TABLE `calcms_roles` ADD COLUMN `edit_help_texts` INT(1) UNSIGNED NOT NULL;
+
+-- admin roles
+ALTER TABLE `calcms_roles` ADD COLUMN `admin` INT(1) UNSIGNED NOT NULL DEFAULT 0 AFTER `level`;
+update calcms_roles set admin=1 where role = 'Admin';