Merge branch 'develop'

* develop:
  FIXED BUG: material is not written into the file stream.
  FIXED BUG: If the passed data is not of vtkPolyData, polydata will be NULL and this NULL is passed to mafVMEPointSet::SetData, which is wrong and will cause ASSERT in DEBUG mode crippling unit tests.
Updated CMake for VS2012
Merge branch 'VS2012Support' into develop