Merge topic 'keep-gdal-nodatavalue'

bf1cd7e2 Change iterator from postincrement to preincrement
5c97e44a Move variable declaration inside loop to limit its scope
5e1fc1bf Fix indentation and restore empty line
761a643e Add field data to vtkUniformGrid to save GDALDataset NoDataValue

Acked-by: Kitware Robot <kwrobot@kitware.com>
Merge-request: !344