Appends menu items to a given menu (not a popup menu) to implement the standard editor operations, such as cut and paste. The callback for each menu item uses get-edit-target-object in top-level-window<%> (finding the frame by following a chain of parents until a frame is reached); if the result is an editor<%> object, do-edit-operation in editor<%> is called on the editor.
If text-only? is #f, then menu items that insert non-text snips (such as Insert Image...) are appended to the menu.