Revise CreateMenuItems to support append mode in addition to reset
Revise CreateMenuItems to support append mode in addition to reset

larsbrubaker/MatterControl,mmoening/MatterControl,mmoening/MatterControl,unlimitedbacon/MatterControl,unlimitedbacon/MatterControl,unlimitedbacon/MatterControl,larsbrubaker/MatterControl,jlewin/MatterControl,jlewin/MatterControl,mmoening/MatterControl,larsbrubaker/MatterControl,unlimitedbacon/MatterControl,larsbrubaker/MatterControl,jlewin/MatterControl,jlewin/MatterControl