BUG: fixed bug #12693, changed PI to use vtkMath pi
BUG: fixed bug #12693, changed PI to use vtkMath pi

Change-Id: Ibbc4b63433a87892ed31d09b58b34b71116d34a9

ashray/VTK-EVM,cjh1/VTK,spthaolt/VTK,johnkit/vtk-dev,gram526/VTK,mspark93/VTK,ashray/VTK-EVM,sumedhasingla/VTK,berendkleinhaneveld/VTK,SimVascular/VTK,jmerkow/VTK,msmolens/VTK,sumedhasingla/VTK,collects/VTK,ashray/VTK-EVM,keithroe/vtkoptix,cjh1/VTK,sumedhasingla/VTK,hendradarwin/VTK,collects/VTK,gram526/VTK,candy7393/VTK,sankhesh/VTK,mspark93/VTK,sankhesh/VTK,berendkleinhaneveld/VTK,demarle/VTK,ashray/VTK-EVM,candy7393/VTK,spthaolt/VTK,berendkleinhaneveld/VTK,demarle/VTK,aashish24/VTK-old,hendradarwin/VTK,spthaolt/VTK,mspark93/VTK,jmerkow/VTK,demarle/VTK,hendradarwin/VTK,msmolens/VTK,collects/VTK,aashish24/VTK-old,SimVascular/VTK,msmolens/VTK,biddisco/VTK,spthaolt/VTK,cjh1/VTK,johnkit/vtk-dev,sankhesh/VTK,SimVascular/VTK,SimVascular/VTK,gram526/VTK,keithroe/vtkoptix,biddisco/VTK,msmolens/VTK,SimVascular/VTK,hendradarwin/VTK,keithroe/vtkoptix,collects/VTK,keithroe/vtkoptix,mspark93/VTK,johnkit/vtk-dev,berendkleinhaneveld/VTK,ashray/VTK-EVM,mspark93/VTK,biddisco/VTK,jmerkow/VTK,johnkit/vtk-dev,hendradarwin/VTK,candy7393/VTK,spthaolt/VTK,sankhesh/VTK,jmerkow/VTK,hendradarwin/VTK,SimVascular/VTK,jmerkow/VTK,gram526/VTK,SimVascular/VTK,msmolens/VTK,msmolens/VTK,msmolens/VTK,keithroe/vtkoptix,sumedhasingla/VTK,sumedhasingla/VTK,jmerkow/VTK,mspark93/VTK,aashish24/VTK-old,jmerkow/VTK,ashray/VTK-EVM,demarle/VTK,sankhesh/VTK,sumedhasingla/VTK,gram526/VTK,sankhesh/VTK,mspark93/VTK,hendradarwin/VTK,keithroe/vtkoptix,cjh1/VTK,biddisco/VTK,berendkleinhaneveld/VTK,ashray/VTK-EVM,candy7393/VTK,sumedhasingla/VTK,keithroe/vtkoptix,candy7393/VTK,biddisco/VTK,jmerkow/VTK,biddisco/VTK,keithroe/vtkoptix,johnkit/vtk-dev,cjh1/VTK,ashray/VTK-EVM,aashish24/VTK-old,berendkleinhaneveld/VTK,candy7393/VTK,sumedhasingla/VTK,msmolens/VTK,aashish24/VTK-old,candy7393/VTK,sankhesh/VTK,demarle/VTK,aashish24/VTK-old,berendkleinhaneveld/VTK,candy7393/VTK,collects/VTK,spthaolt/VTK,gram526/VTK,johnkit/vtk-dev,mspark93/VTK,SimVascular/VTK,demarle/VTK,biddisco/VTK,spthaolt/VTK,gram526/VTK,gram526/VTK,johnkit/vtk-dev,demarle/VTK,sankhesh/VTK,demarle/VTK,cjh1/VTK,collects/VTK