HAVANA (AP) — An impromptu sit-in protest at the steps of Havana University on Monday drew a small group of students concerned about their education amid an energy crisis worsened by a U.S. oil blockade of the island, which has reduced classes and is paralyzing the country. Power outages and transportation shutdowns have forced the university to reduce the number of classes or hold them online, though many students are also struggling with slow and unreliable internet. “We aren’t martyrs for