For three years in the early 1990s, in the wake of the breakup of Yugoslavia, this small country in the Balkans was constantly in the news because of the brutal civil war it suffered between the Muslim Bosniaks and the Orthodox Christian Bosnian Serbs. It has been at peace since December 1995, and more travelers have been discovering its myriad natural, historical, and cultural appeals. But others come for "dark tourism," a trend which involves visiting places associated with tragedy