Converts an absolute path into a path relative to a base path.
static CL_String CL_PathHelp::make_relative( const CL_String & base_path, const CL_String & absolute_path, PathType path_type = path_type_file );
Detailed description:
CL_String str = CL_PathHelp::make_relative ("ABD/DEF/", "c:\user\ABD\Filename.txt", CL_PathHelp::path_type_file ); On Windows: str = "..\Filename.txt"