KWSys: Tell Git not to export .gitattributes
KWSys: Tell Git not to export .gitattributes

KWSys upstream added an attribute to export .gitattributes so that
importing snapshots into the sources of other projects would bring along
the attributes.  However, we don't want to export them from VTK.
Drop .gitattributes entries not relevant to VTK.

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