Once the home of the highest railroad in the world, two sisters have restored the tiny town back to a San Luis Valley gem. — By Kara Mason In the 1880s, before rollercoasters and theme parks were widely popular, there was another way for people to get their adrenaline fix: the world’s highest operating train, dubbed the “railroad above the clouds” near La Veta in Southern Colorado. “It was like the Six Flags of America,”…