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/site/files/css/messaging.css

@@ -0,0 +1,4 @@
+.messaging-box fieldset {
+  overflow: scroll;
+  height: 250px;
+}

modules/messaging/site/files/scss/messaging.scss

@@ -0,0 +1,6 @@
+.messaging-box {
+	fieldset {
+		overflow:scroll; 
+		height:250px;
+	}
+}