TEST: Setting the TInternalPrecision template parameter of the filter to double so as to fall back to the old filter behaviour for testing (test still passing)

ENH: Simplifying gdal reading nominal case: no more post-read de-interleave operation, only one RasterIO call is done

ENH: Patching GdalImageIO to simplify streaming write: avoid unnecessary memory allocation, avoiding to de-interleave data before writing, using a single RasterIO call