Setting the GeoTransform parameters doesn't work on the Intergraph format

[DaveOke]

If the user creates a new Intergraph formatted raster file, calling set geotransform doesn't carry though from the dataset to the raster band, resulting in an incorrect transformation matrix being encoded in the resultant intergraph .grd file.

We fixed temporarly by adding in the IntergraphRasterBand::FlushBandHeader function the ability to copy the transformation matrix from the dataset, only it a transformation matrix has been set, to the raster band before the headers are written.