Irada Humbatova/Reuters The case of two Swedish journalists imprisoned in Ethiopia sheds light on a harsh campaign of repression. By NICHOLAS D. KRISTOF | New York Times   DAVOS, Switzerland On the Ground Damon Winter/The New York Times Nicholas D. Kristof IN a filthy Ethiopian prison that is overridden with lice, fleas and huge rats, two Swedes are serving an 11-year...