add SSL support to VTKWeb server
add SSL support to VTKWeb server

New command-line arguments allow us to serve VTKWeb content
over secure websockets.

Change-Id: Ieb5bb9c5a4387bd9ec6c738546f3622480b7b2f1

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