Moved filter of nodes of type blog to the node storage layer.

This is more efficient because the result set from the query will be smaller and it will be easier to implement the pagination

modules/node/cms_node_api.e

@@ -212,10 +212,10 @@ feature -- Access: Node
 			Result := node_storage.nodes
 		end
 
-	nodes_order_created_desc: LIST[CMS_NODE]
+	blogs_order_created_desc: LIST[CMS_NODE]
 			-- List of nodes ordered by creation date (descending)
 		do
-			Result := node_storage.nodes_order_created_desc
+			Result := node_storage.blogs
 		end
 
 	recent_nodes (a_offset, a_rows: INTEGER): LIST [CMS_NODE]