verify-tag: make it operable from a subdirectory.

Signed-off-by: Junio C Hamano <junkio@cox.net>

git-verify-tag.sh

@@ -1,5 +1,6 @@
 #!/bin/sh
-. git-sh-setup
+
+GIT_DIR=`git-rev-parse --git-dir` || exit $?
 
 type="$(git-cat-file -t "$1" 2>/dev/null)" ||
 	die "$1: no such object."
@@ -7,6 +8,9 @@ type="$(git-cat-file -t "$1" 2>/dev/null)" ||
 test "$type" = tag ||
 	die "$1: cannot verify a non-tag object of type $type."
 
-git-cat-file tag "$1" > .tmp-vtag || exit 1
-cat .tmp-vtag | sed '/-----BEGIN PGP/Q' | gpg --verify .tmp-vtag - || exit 1
-rm -f .tmp-vtag
+git-cat-file tag "$1" >"$GIT_DIR/.tmp-vtag" || exit 1
+cat "$GIT_DIR/.tmp-vtag" |
+sed '/-----BEGIN PGP/Q' |
+gpg --verify "$GIT_DIR/.tmp-vtag" - || exit 1
+rm -f "$GIT_DIR/.tmp-vtag"
+