Resolve "ExtractROI: keep GCPs"
Due to GDAL limitations, we only save GCP when there is no projectionRef or imageKeywordlist.
Because the geotransform is not saved with the GCPs, the GCP image coordinates are adapted if the image has non-default origin/spacing values.
The test apTvUtQuicklookWithGCP has been added to check this behaviour.
Closes #1937 (closed)