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.

examples/demo/site/modules/admin/files/scss/admin.scss

@@ -12,7 +12,7 @@ ul.cms-users {
 	}
 
 	li.cms_user a::before {
-		content: "[users] ";
+		content: "[user] ";
 	}
 }
 
@@ -31,7 +31,7 @@ ul.cms-roles {
 	}
 
 	li.cms_role a::before {
-		content: "[roles] ";
+		content: "[role] ";
 	}
 }