fix index out-of-range exception in LogSyncThread
fix index out-of-range exception in LogSyncThread

gizatt/director,openhumanoids/director,mithrandir123/director,mitdrc/director,mithrandir123/director,edowson/director,RussTedrake/director,mitdrc/director,RobotLocomotion/director,manuelli/director,empireryan/director,rdeits/director,empireryan/director,gizatt/director,manuelli/director,openhumanoids/director,mitdrc/director,empireryan/director,RobotLocomotion/director,patmarion/director,openhumanoids/director,rdeits/director,mithrandir123/director,rdeits/director,patmarion/director,patmarion/director,RussTedrake/director,RobotLocomotion/director,gizatt/director,openhumanoids/director,RobotLocomotion/director,edowson/director,RussTedrake/director,rdeits/director,mitdrc/director,openhumanoids/director,empireryan/director,gizatt/director,manuelli/director,manuelli/director,edowson/director,gizatt/director,patmarion/director,mithrandir123/director,RussTedrake/director,mitdrc/director,patmarion/director,manuelli/director,edowson/director,edowson/director,empireryan/director,RussTedrake/director,rdeits/director,mithrandir123/director,RobotLocomotion/director