Harvard sued and asked for a restraining order less than 24 hours after the Trump administration had said it would block current and future international students from attending the university. Harvard University sued the Trump administration on Friday, less than 24 hours after the Department of Homeland Security said it would block international students from attending the nation’s oldest university and one of its most prestigious. Later Friday morning, at the university’s request, a federal judge in Boston moved swiftly to block implementation of the federal government’s order. The judge,…