Add Slice Along Polyline filter to ParaView

This commit adds a filter to slice along a poly-line.  The filter is in
the VTKExtensions/Default module and it is accessible from the filters
menu in ParaView.

Change-Id: I384b77c1eab70d15e7e232a8bea02d16649f72de
Fixed incorrect input-data type and parallel processing.

* Use INPUT_REQUIRED_DATA_TYPE() to specify required input types.
* Use vtkPProbeFilter to ensure probing works in parallel.

Change-Id: I64dea11185710c26afbe17425b34106e6230b36a
Add test for testing SliceAlongPolyline filter.

Change-Id: I9afe8a1cd80f9bb4ad8ba88381fa6cf060f6385f
Explicitly handle composite datasets.

This avoid duplicated processing of input polyline as well as laying
ground work for handling cases where the input polyline is split among
ranks (when running in parallel).

Change-Id: I94f1c24b5d807c1d329fcebb1179d529a288a00c
Fix parallel processing in vtkSliceAlongPolyPlane.

Ensures that vtkSliceAlongPolyPlane communicates the input polyline to
all ranks before attempting to probe into the dataset. Had to move the
vtkSliceAlongPolyPlane to ClientServerCore/Default since we need access
to vtkMPIMoveData filter to make it easier to communicate datasets.

Change-Id: I7ad5ce66297bb9094d0caf108af0f234eae019a5
Merge topic 'slice_along_polyline' into next

a507b102 Fix parallel processing in vtkSliceAlongPolyPlane.
b4c908dd Explicitly handle composite datasets.
f186ea7a Add test for testing SliceAlongPolyline filter.
cddc8e22 Fixed incorrect input-data type and parallel processing.
36f24a36 Add Slice Along Polyline filter to ParaView