vtkPVWebApplication: support bypassing base64 encoding
Requires a new method call, because a string isn't suitable for returning a binary buffer from VTK to python. Use a vtkDataArray, then a memoryview to convert to bytes. Working in Python 2.7, 3
Fixes some path issues with mis-matched slashes, and a threading crash on windows with a timing hack until we can identify the issue.
Fix Py3 division to produce an int where needed.
Depends on VTK MR vtk/vtk!3117 (merged)
@sebastien.jourdain Paraview portion.
Edited by Aron Helser