A Greek court on Wednesday declared neo-Nazi party Golden Dawn a criminal group, effectively banning a radical organisation that was once the third-largest political force in the country.The judgment came as police and anti-fascist demonstrators clashed outside the courthouse, on the sidelines of a large protest of some 15,000 people.Reading out the verdict in a trial that took place over five years, presiding judge Maria Lepenioti said Golden Dawn founder and leader Nikos Michaloliakos and…