Turret system null exception?

[pvutov]

With version 8fae01f , reported by MarinusTau

• Following error is becoming more common and pauses the game, now with fasttank and marines and riflemen:
  NullReferenceException: Object reference not set to an instance of an object
  PFW.Units.Component.Weapon.TurretSystem.Update () (at Assets/Units/Component/Weapon/TurretSystem.cs:103)
  --- Error possibly also came at AOE destruction of a kamaz truck?
  --- Another hunch: rotation beyond 90° seem to also cause it? <- maybe rotation around wrong axis causes error`?