A Montana motorcyclist who was missing for five days after crashing along an Idaho mountain highway survived by drinking creek water until he was found, authorities say.Video above: Gizmo the dog went missing in Las Vegas in 2015. He’s been found alive after 9 yearsZachary Demoss, 24, was badly injured in the crash, but “was tough enough to hold out for five days on that mountain while he’d seen people walking by, trying to holler at them,” family friend Greg Common told Boise television station KTVB. Demoss’ shouting went unanswered until Common caught sight of him while searching five days after the Aug. 11 crash.”It was surreal that we found him,” Common said. “Something just willed me to look right, and there he was, laying right there by the river.”Demoss had been riding his 2000 Kawasaki Vulcan motorcycle along Highway 12 with two other people. After the other travelers saw …