Improved node management.

- List node by node types
- fixed the trash/restore/delete workflow
Added messaging module to send message to cms users (by email for now).
Added early protection for cache, export and import functionalities.

modules/messaging/src/cms_messaging_api.e

@@ -0,0 +1,17 @@
+note
+	description: "API for the contact module."
+	date: "$Date$"
+	revision: "$Revision$"
+
+class
+	CMS_MESSAGING_API
+
+inherit
+	CMS_MODULE_API
+
+	REFACTORING_HELPER
+
+create
+	make
+
+end