Add MPI based Web sample application

The ParallelViz Web application provide an example
on how to setup a ParaViewWeb application for Parallel visualization.

The default example use a dummy sphere source colored by process id.

Change-Id: I0cf60b9fcebcf51d8cd69b222f24301fffd0c52c
Merge topic 'add-parallel-web-demo' into next

8027621 Add MPI based Web sample application