Make the Copy/Move actions in the message reader window work consistently
That is, consistently with those in the main KMail window. Use those main window actions to set the text and icon, so that the icon fallback implemented in Akonadi::StandardActionManager works. Save the folder used for a copy or move action in the recently used folder list so that the list is updated even though we are not using the standard Akonadi actions.
This MR will not compile unless akonadi!57 (merged) is implemented first.