By ISABEL INFANTES / AFP A central London district famous for its nightlife, but also home to thousands of residents, is trying out a novel way to tackle the persistent problem of public urination: so-called anti-pee paint. A central London district famous for its nightlife, but also home to thousands of residents, is trying out a novel way to tackle the persistent problem of public urination: so-called anti-pee paint. Officials in Soho — a warren of bars, restaurants, theatres and other entertainment venues as well as apartments and houses — are treating walls at nearly a dozen problem site…