Added virtual destructor.
Added virtual destructor.

cjh1/VTK,biddisco/VTK,ashray/VTK-EVM,spthaolt/VTK,berendkleinhaneveld/VTK,gram526/VTK,johnkit/vtk-dev,demarle/VTK,berendkleinhaneveld/VTK,demarle/VTK,biddisco/VTK,gram526/VTK,collects/VTK,Wuteyan/VTK,hendradarwin/VTK,aashish24/VTK-old,SimVascular/VTK,gram526/VTK,msmolens/VTK,demarle/VTK,daviddoria/PointGraphsPhase1,jmerkow/VTK,naucoin/VTKSlicerWidgets,jmerkow/VTK,gram526/VTK,mspark93/VTK,jeffbaumes/jeffbaumes-vtk,biddisco/VTK,jmerkow/VTK,sumedhasingla/VTK,naucoin/VTKSlicerWidgets,candy7393/VTK,johnkit/vtk-dev,daviddoria/PointGraphsPhase1,sankhesh/VTK,keithroe/vtkoptix,demarle/VTK,mspark93/VTK,mspark93/VTK,johnkit/vtk-dev,candy7393/VTK,spthaolt/VTK,biddisco/VTK,jmerkow/VTK,sgh/vtk,biddisco/VTK,collects/VTK,cjh1/VTK,Wuteyan/VTK,sgh/vtk,jeffbaumes/jeffbaumes-vtk,cjh1/VTK,jmerkow/VTK,arnaudgelas/VTK,candy7393/VTK,demarle/VTK,mspark93/VTK,sgh/vtk,Wuteyan/VTK,gram526/VTK,naucoin/VTKSlicerWidgets,sankhesh/VTK,arnaudgelas/VTK,daviddoria/PointGraphsPhase1,msmolens/VTK,ashray/VTK-EVM,msmolens/VTK,candy7393/VTK,SimVascular/VTK,mspark93/VTK,sumedhasingla/VTK,johnkit/vtk-dev,collects/VTK,berendkleinhaneveld/VTK,mspark93/VTK,biddisco/VTK,sankhesh/VTK,collects/VTK,SimVascular/VTK,msmolens/VTK,hendradarwin/VTK,arnaudgelas/VTK,aashish24/VTK-old,aashish24/VTK-old,candy7393/VTK,mspark93/VTK,arnaudgelas/VTK,candy7393/VTK,gram526/VTK,sumedhasingla/VTK,SimVascular/VTK,keithroe/vtkoptix,berendkleinhaneveld/VTK,sumedhasingla/VTK,hendradarwin/VTK,biddisco/VTK,keithroe/vtkoptix,collects/VTK,cjh1/VTK,demarle/VTK,sgh/vtk,sankhesh/VTK,aashish24/VTK-old,ashray/VTK-EVM,naucoin/VTKSlicerWidgets,demarle/VTK,SimVascular/VTK,daviddoria/PointGraphsPhase1,sankhesh/VTK,johnkit/vtk-dev,spthaolt/VTK,sumedhasingla/VTK,cjh1/VTK,ashray/VTK-EVM,ashray/VTK-EVM,hendradarwin/VTK,spthaolt/VTK,Wuteyan/VTK,mspark93/VTK,spthaolt/VTK,keithroe/vtkoptix,johnkit/vtk-dev,sankhesh/VTK,msmolens/VTK,msmolens/VTK,johnkit/vtk-dev,Wuteyan/VTK,hendradarwin/VTK,arnaudgelas/VTK,jeffbaumes/jeffbaumes-vtk,sumedhasingla/VTK,sumedhasingla/VTK,collects/VTK,SimVascular/VTK,sgh/vtk,sgh/vtk,naucoin/VTKSlicerWidgets,SimVascular/VTK,berendkleinhaneveld/VTK,arnaudgelas/VTK,hendradarwin/VTK,keithroe/vtkoptix,cjh1/VTK,jmerkow/VTK,jmerkow/VTK,sumedhasingla/VTK,Wuteyan/VTK,aashish24/VTK-old,keithroe/vtkoptix,ashray/VTK-EVM,berendkleinhaneveld/VTK,msmolens/VTK,sankhesh/VTK,keithroe/vtkoptix,sankhesh/VTK,berendkleinhaneveld/VTK,jeffbaumes/jeffbaumes-vtk,aashish24/VTK-old,ashray/VTK-EVM,jeffbaumes/jeffbaumes-vtk,jeffbaumes/jeffbaumes-vtk,candy7393/VTK,daviddoria/PointGraphsPhase1,demarle/VTK,msmolens/VTK,spthaolt/VTK,ashray/VTK-EVM,candy7393/VTK,SimVascular/VTK,naucoin/VTKSlicerWidgets,gram526/VTK,jmerkow/VTK,hendradarwin/VTK,gram526/VTK,daviddoria/PointGraphsPhase1,Wuteyan/VTK,keithroe/vtkoptix,spthaolt/VTK