Move libraries layout', model', `peristence' under cms folder

Updated code to the new layout.
Added missing comments.
Remove /example/api

cms/persistence/implementation/mysql/scripts/triggers.sql

@@ -0,0 +1,8 @@
+DELIMITER $$
+CREATE TRIGGER update_editor
+AFTER INSERT ON `users_nodes` FOR EACH ROW
+   UPDATE Nodes
+     SET editor_id = NEW.users_id
+   WHERE id = NEW.nodes_id;
+$$
+DELIMITER ;