ENH: Added test for vtkMFIXReader

Added a test for MFIXReader. Sample dataset provided by Terry Jordan.

Change-Id: Ib1f2b37d8882550260fc35d5e5c9967f01983c51
Merge topic 'Coverage_MFIXReader' into master

e38e93f4 ENH: Added test for vtkMFIXReader