This morning Gush Shalom, the Israeli Peace Bloc, had the doubtful honor of being chosen as the target of a verbal broadside by Justice Minister Meir Sheetrit. The minister was apparently ired by the Jan.9 forum discussion on war crimes held under Gush Shalom auspices at the Tzavta Hall in Tel-Aviv, and particularly at the suggestion made by several speakers that peace-seeking Israeli groups start preparing war crime dossiers against military officers known to have ordered or carried out specific violations of international law