implement OSPVariant::toString()
implement OSPVariant::toString()

MengjiaoH/ospray,wilsonCernWq/ospray,MengjiaoH/ospray,wilsonCernWq/ospray,ospray/OSPRay,MengjiaoH/ospray,ospray/OSPRay,wilsonCernWq/ospray,ospray/OSPRay,ospray/OSPRay,MengjiaoH/ospray,MengjiaoH/ospray