Add SMP support to more transform classes

SMP acceleration has been implemented for nearly all of the VTK transform classes (that is, classes derived from vtkAbstractTransform). Previously only vtkTransform and similar vtkLinearTransform-derived classes were accelerated. Implemented now: vtkIdentityTransform, vtkGridTransform, vtkBSplineTransform, vtkThinPlateSplineTransform, vtkPerspectiveTransform, vtkCylindricalTransform, and vtkSphericalTransform.