Warn when trying to set an invalid date for the OGR data model (i.e. year > 32767 or < -32768); also warn when trying to warn an invalid date for the DBF format (i.e. year < 0 or year > 9999)

git-svn-id: https://svn.osgeo.org/gdal/trunk@25473 f0d54148-0727-0410-94bb-9a71ac55c965