text: 12 Nepalese Hostages Said Slain in Iraq BAGHDAD, Iraq - A gruesome video posted on a Web site purported to show militants beheading a Nepalese worker and shooting 11 others in the first mass slaying of foreign hostages during the Iraqi insurgency.    If confirmed, it would raise the number of foreign workers known to have been slain by extremists to at least 22 in a terror campaign aimed at forcing foreign troops and contract workers out of the country....