Added support for dateline offset to provide users with capability to set different offsets than 170 to -170 (#4098)
Added new key to ogr2ogr -datelineoffset and fix dox file

git-svn-id: https://svn.osgeo.org/gdal/trunk/gdal@25642 f0d54148-0727-0410-94bb-9a71ac55c965