Ajout de la création du schéma SQL requis.

data/schema.sql

+CREATE TABLE IF NOT EXISTS `user_role` (
+  `role_id` varchar(255) NOT NULL,
+  `default` tinyint(1) NOT NULL,
+  `parent` varchar(255) DEFAULT NULL,
+  PRIMARY KEY (`role_id`)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8;
+
+CREATE TABLE IF NOT EXISTS `user_role_linker` (
+  `user_id` int(11) unsigned NOT NULL,
+  `role_id` varchar(255) NOT NULL,
+  PRIMARY KEY (`user_id`,`role_id`),
+  KEY `role_id` (`role_id`)
+) ENGINE=InnoDB DEFAULT CHARSET=utf8;