RC Lens have reportedly named the transfer fee needed for Rangers to sign winger Oscar Cortes permanently this summer. The 20-year-old Colombian winger was recruited by Ibrox manager Philippe Clement in January from the the French side on loan until the end of the season. And he got off to a promising start in Glasgow by racking up three goal contributions in his first seven games for the Light Blues, as per Transfermarkt. However, an unfortunate hamstring injury was picked up in the Scottish Premiership victory over Kilmarnock in March and that brought his season to a premature end. But his s…