our in-tree GNU tar (gnu/usr.bin/tar) is way too old and has security
	problems.  therefore, upgrade is necessary.

	i've prepared new GNU tar under gnu/usr.bin/tar.new (and gnu/dist/tar),
	with security fixes in place, and plan to switch to tar.new (either
	by tweaking Makefile, or by overwriting gnu/usr.bin/tar by tar.new)
	soon.  some of the command line options (not the major ones) are
	obsoleted, or changed, due to the upgrade.

itojun

PS: forget about "we need to migrate to pax" discussion for now.
pax problem is being handled separately, and we need to secure GNU tar in
our tree anyways (until pax takes over).