Train enthusiast Joe Biden unveiled a $8.2 billion plan Friday to get America’s creaking rail network back on track, including its first ever high-speed link between Los Angeles and Las Vegas. Slow, infrequent and often non-existent, trains have long been the poor relation of cars and planes in the United States. But the US president, who used the train between his Delaware home and Washington so much as a US senator that he was nicknamed “Amtrak Joe,” visited Las Vegas to announce a series of federally funded rail upgrades. “You have no idea how much this pleases me,” Biden said…