GNU coding standards. Remove --license.
* gnulib.modules: Add version-etc-fsf.
* doc/tar.texi: Document the change.
* lib/.cvsignore: Add version-etc-fsf.c, version-etc.c, version-etc.h.
* scripts/Makefile.am (SED_CMD): Update PAKCAGE_NAME, not PACKAGE.
* scripts/backup.in: Remove --license. Change --version to conform
to GCS.
* scripts/restore.in: Likewise.
* scripts/backup.sh.in (license): Output briefer license in the
style of coreutils, for consistency with other changes.
* src/tar.c: Include <version-etc.h>.
(LICENSE_OPTION): Remove.
(options): Remove --license.
(license): Remove.
(parse_opt): Use version_etc instead of rolling it ourselves.
Remove --license.
* tests/version.at (tar --version): Check only the first line of
output.
