Added RasterSource/GDALBand GDAL objects

Based on Daniel Wiesmann's raster branch. Refs #23804.
I am not sure if this is the right regex, as it is imported from geometry.regex. I would say it is, thats why I used it here originally. But I am not certain and not very familiar with regexes. Maybe this option could be left away for now until a function to translate from WKB and a capi ptr is included. 

A related question is what wkb to use for rasters. As far as I know, the definition of a raster wkb is not as established as the WKBs for geometries. I would propose to use the PostGIS definition, but maybe there are others.