Ewan McGregor wants Scots heroin users to try a drug-free treatment to break the cycle of addiction.The actor, who played Mark Renton in Trainspotting, urged the Scottish Government to investigate neuro electric therapy after narrating a documentary charting successful trials in the US.NET was developed in the 70s by Hong Kong-based Scots surgeon Meg Patterson, whose previous patients included rock stars Eric Clapton, Keith Moon and Boy George.It uses tiny pulses of electrical currents to