AUTHOR HARRY M. CAUDILL, whose book "Night Comes to the Cumberlands" helped inspire President Johnson's war on poverty, fatally shot himself Thursday in at his home in Whitesburg, Ky. He was 68 . . . SOME 1,500 left-wing Filipinos rallied outside the U.S. Embassy Friday to demand the dismantling of American military bases in the country after a treaty covering their stay expires next year . . . FORTY-FOUR VIETNAMESE boat people left Thailand Friday under a voluntary repatriation program organized and supported by the U.N. High Commissioner for Refugees, a press statement said.