Seems a large commit, but I also changed function names to match the new

naming convention for Compositing:

- Render Result node -> Render Layers node (name only appears in Add menu)
- Compositor image -> Viewer Node image

I've also added a version patch (2.41 saved files only) to rename existing
"Compositor" Images.

source/blender/src/header_node.c

@@ -442,8 +442,8 @@ static void do_node_nodemenu(void *arg, int event)
 		case 7: /* hide/unhide */
 			node_hide(snode);
 			break;
-		case 8: /* read saved render results */
-			node_read_renderresults(snode);
+		case 8: /* read saved render layers */
+			node_read_renderlayers(snode);
 			break;
 		case 9: /* show cyclic */
 			ntreeSolveOrder(snode->edittree);