Fixed mismatches cell arrays in vtkPStreamTracer.

vtkPStreamTracer was not consistently generating cell arrays on all ranks. The
ReasonForTermination array was missing on occasion. This was causing segfaults
when rendering translucent streamlines in ParaView since several pipelines
assume that data arrays match across all processes. This fixes that issue. We
were missing adding of the ReasonForTermination for the exception case where the
integration resulted in a single point streamline.

Change-Id: I6071020947b05bdca30dbeb1cfb8df28776b568f
Merge topic 'fix_parallel_streamtracer_mismatched_arrays' into master

d616545b Fixed mismatches cell arrays in vtkPStreamTracer.