refactor: it => pillar_it (CURA-3238)
refactor: it => pillar_it (CURA-3238)

Ultimaker/CuraEngine,alephobjects/CuraEngine,ROBO3D/CuraEngine,alephobjects/CuraEngine,Ultimaker/CuraEngine,alephobjects/CuraEngine,ROBO3D/CuraEngine,ROBO3D/CuraEngine