Removed unused sstream include, add Windows logic
Removed unused sstream include, add Windows logic

Windows define for snprintf was missing, the sstream inlude is no
longer being used.

SimVascular/VTK,keithroe/vtkoptix,candy7393/VTK,candy7393/VTK,sankhesh/VTK,msmolens/VTK,candy7393/VTK,SimVascular/VTK,gram526/VTK,candy7393/VTK,sumedhasingla/VTK,sankhesh/VTK,sumedhasingla/VTK,msmolens/VTK,sankhesh/VTK,mspark93/VTK,candy7393/VTK,SimVascular/VTK,gram526/VTK,keithroe/vtkoptix,mspark93/VTK,keithroe/vtkoptix,msmolens/VTK,gram526/VTK,sumedhasingla/VTK,demarle/VTK,sankhesh/VTK,sumedhasingla/VTK,msmolens/VTK,SimVascular/VTK,demarle/VTK,msmolens/VTK,msmolens/VTK,gram526/VTK,demarle/VTK,sumedhasingla/VTK,demarle/VTK,candy7393/VTK,jmerkow/VTK,gram526/VTK,gram526/VTK,mspark93/VTK,keithroe/vtkoptix,keithroe/vtkoptix,gram526/VTK,msmolens/VTK,SimVascular/VTK,mspark93/VTK,sumedhasingla/VTK,jmerkow/VTK,demarle/VTK,jmerkow/VTK,SimVascular/VTK,jmerkow/VTK,sumedhasingla/VTK,jmerkow/VTK,candy7393/VTK,SimVascular/VTK,gram526/VTK,demarle/VTK,jmerkow/VTK,sumedhasingla/VTK,keithroe/vtkoptix,keithroe/vtkoptix,demarle/VTK,mspark93/VTK,keithroe/vtkoptix,demarle/VTK,mspark93/VTK,sankhesh/VTK,mspark93/VTK,jmerkow/VTK,mspark93/VTK,jmerkow/VTK,msmolens/VTK,SimVascular/VTK,sankhesh/VTK,candy7393/VTK,sankhesh/VTK,sankhesh/VTK