minor change in new-grid-update

sails/src/CHANGES.md

 # Changes for new grid system
 
--- Rename columns
-RENAME TABLE `scene` TO `grid`;
-ALTER TABLE `stu_picto` CHANGE `id_scene` `id_grid` int(11) NOT NULL;
-ALTER TABLE `student` CHANGE `id_active_scene` `id_active_grid` int(11) NULL;
-
--- Add new column 'id_child_grid'
-ALTER TABLE `stu_picto` ADD `id_child_grid` int(11) NULL;
-
--- Drop column 'categories'
-ALTER TABLE `grid` DROP COLUMN `categories`;
-
--- Add color to grid column
-ALTER TABLE `grid` ADD `color` varchar(7) NULL;
-
--- Foreign key stu_picto(id_child_grid) <- grid(id)
-ALTER TABLE stu_picto ADD FOREIGN KEY(id_child_grid) REFERENCES grid(id) ON DELETE SET NULL;
+Solo hay que lanzar, desde MySQL el archivo roles/database/files/new-grid-system-adapt.sql