git-sh-setup: be explicit where to dot-source git-sh-i18n from.

d323c6b6 ("i18n: git-sh-setup.sh: mark strings for translation",
2016-06-17) started to dot-source git-sh-i18n shell script library,
assuming that $PATH is already adjusted for our scripts, namely,
$GIT_EXEC_PATH is at the beginning of $PATH.

Old contrib scripts like contrib/convert-grafts-to-replace-refs.sh
and contrib/rerere-train.sh and third-party scripts like guilt may
however be using this as ". $(git --exec-path)/git-sh-setup",
without satisfying that assumption.  Be more explicit by specifying
its path prefixed with "$(git --exec-path)/". to be safe.

While we’re here, move the sourcing of git-sh-i18n below the shell
portability fixes.
Signed-off-by: NAnders Kaseorg <andersk@mit.edu>
Signed-off-by: NJunio C Hamano <gitster@pobox.com>

git-sh-setup.sh

@@ -2,9 +2,6 @@
 # to set up some variables pointing at the normal git directories and
 # a few helper shell functions.
 
-# Source git-sh-i18n for gettext support.
-. git-sh-i18n
-
 # Having this variable in your environment would break scripts because
 # you would cause "cd" to be taken to unexpected places.  If you
 # like CDPATH, define it for your interactive shell sessions without
@@ -46,6 +43,9 @@ git_broken_path_fix () {
 
 # @@BROKEN_PATH_FIX@@
 
+# Source git-sh-i18n for gettext support.
+. "$(git --exec-path)/git-sh-i18n"
+
 die () {
 	die_with_status 1 "$@"
 }