OGRSpatialReference::Validate() : in addition to hand-validation, use WKT grammar from OGC 01-009 CT

git-svn-id: https://svn.osgeo.org/gdal/trunk@26291 f0d54148-0727-0410-94bb-9a71ac55c965
Merge branch 'trunk' into trunk_travis_macosx