GENEVA (Reuters) - Former Bosnian Serb army commander Ratko Mladic is the  epitome of evil  and his conviction on Wednesday for genocide, crimes against humanity and war crimes was a  momentous victory for justice , U.N. human rights chief Zeid Ra ad al-Hussein said.   Mladic is the epitome of evil, and the prosecution of Mladic is the epitome of what international justice is all about,  Zeid said in a statement.  Today s verdict is a warning to the perpetrators of such crimes that they will not escape justice, no matter how powerful they may be nor how long it may take.  