ECW: integrate GDAL_ECW_5.0.3.patch with a few adjustments ( compilation fix for NCSecwSetConfig(NCSCFG_PROJECTION_FORMAT, NCS_PROJECTION_ERMAPPER_FORMAT) not available in SDK 4.x; logic to detect RGB or RGBA source input dataset broken; make a copy of strings when filling the papszBandDescriptions array; adjustment in NITF driver to correctly set color interpretation) (#5029)

git-svn-id: https://svn.osgeo.org/gdal/trunk@25784 f0d54148-0727-0410-94bb-9a71ac55c965