When Hamlet asks the gravedigger, “Whose grave’s this, sirrah?” he receives the answer, “Mine.” Nira Pereg’s three-channel video installation “Kept Alive,” 2009-10, filmed at Jerusalem’s Mountain of Rest cemetery (Har Hamenuchot) and shown earlier this year at the Tel Aviv Museum of Art, similarly asks: Whose grave’s this? In Jerusalem, the question is ominously political…