BAGHDAD (Reuters) - A suicide car bomber killed the head of Iraq's Governing Council Monday, increasing fears that instability will make a new Iraqi government unable to function when U.S. occupiers hand it power in six weeks. The killing of Izzedin Salim dealt another major blow to the U.S.-led coalition, battling a Shi'ite Muslim insurgency and a growing scandal over the abuse of Iraqi prisoners. Salim, a Shi'ite who edited several newspapers, was in the last car of a council convoy waiting to enter the "Green Zone" coalition headquarters when the bomb exploded at a checkpoint in central Baghdad, killing...