Update Cocoa GUI example to link to VTK6 rendering libraries.
Update Cocoa GUI example to link to VTK6 rendering libraries.

Change-Id: I2937d5bfd395f200219614b2d779030cf4273bc9

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