Added trash feature: Remove or revert a node.

Added Handler to show the current trash nodes for a given user.
An admin can see all the trash nodes.
Updated storage to handle trash and revert nodes.

modules/node/persistence/cms_node_storage_i.e

@@ -70,6 +70,11 @@ feature -- Access
 		deferred
 		end
 
+	trash_nodes (a_user_id: INTEGER_64): LIST [CMS_NODE]
+			-- List of nodes by user `a_user_id'.
+		deferred
+		end
+
 	recent_nodes (a_lower: INTEGER; a_count: INTEGER): LIST [CMS_NODE]
 			-- List of recent `a_count' nodes with an offset of `lower'.
 		deferred
@@ -135,6 +140,36 @@ feature -- Change: Node
 		deferred
 		end
 
+	trash_node (a_node: CMS_NODE)
+			-- Trash `a_node'.
+		do
+			if a_node.has_id then
+				trash_node_by_id (a_node.id)
+			end
+		end
+
+	revert_node (a_node: CMS_NODE)
+			-- Revert `a_node'.
+		do
+			if a_node.has_id then
+				revert_node_by_id (a_node.id)
+			end
+		end
+
+	trash_node_by_id (a_id: INTEGER_64)
+			-- Trash node by id `a_id'.
+		require
+			valid_node_id: a_id > 0
+		deferred
+		end
+
+	revert_node_by_id (a_id: INTEGER_64)
+			-- Revert node by id `a_id'.
+		require
+			valid_node_id: a_id > 0
+		deferred
+		end
+
 --	update_node_title (a_user_id: like {CMS_USER}.id; a_node_id: like {CMS_NODE}.id; a_title: READABLE_STRING_32)
 --			-- Update node title to `a_title', node identified by id `a_node_id'.
 --			-- The user `a_user_id' is an existing or new collaborator.