Add whitespace around binary operators
Add whitespace around binary operators

As per our code style.

Contributes to issue CURA-2627.

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