[vtkusers] single actor with different cell-colors

[Obada Mahdi]

Hi Jean-Do,

on a quick note, it seems that the "SoilArray" data array is never
being added to the cell field data of m_pMeshPolyData.  After cerating
"m_pSoilArray", try

  m_pMeshPolyData->GetCellData()->AddArray(m_pSoilArray);

HTH,

Obada