By Stephanie van den Berg THE HAGUE (Reuters) -A U.N. tribunal in The Hague opened the genocide trial on Thursday of a Rwandan businessman captured two years ago after decades on the run, with judges saying the hearing must go on despite the suspect’s decision to boycott it from his jail cell. Felicien Kabuga, a former businessman and radio station owner, is one of the last suspects sought by a U.N. tribunal prosecuting crimes committed in the 1994 genocide, when ruling Hutu majority extremists killed more than 800,000 minority Tutsis and Hutu moderates in 100 days. “Mr Kabuga is this morning …