* tools/gpgtar.h (TF_EXTHDR, TF_GEXTHDR): New.
* tools/gpgtar-list.c (parse_header): Set the new type flags.
(parse_extended_header): New.
(read_header): Add arg r_extheader and parse extended header.
(print_header): Consult the extended header.
(gpgtar_list): Pass an extended header object.
(gpgtar_read_header): Ditto.
(gpgtar_print_header): Ditto.
* tools/gpgtar-extract.c (extract): New arg exthdr and factor name
checking out to ...
(check_suspicious_name): new.
(extract_regular): Add arg exthdr and consult it.
(extract_directory): Likewise.
(gpgtar_extract): Provide extheader object.