i18n: git-submodule "Entering [...]" message

Gettextize the "Entering [...]" message. This is explicitly tested for
so we need to skip a portion of a test with test_i18ncmp.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

git-submodule.sh

@@ -306,7 +306,7 @@ cmd_foreach()
 	do
 		if test -e "$path"/.git
 		then
-			say "Entering '$prefix$path'"
+			say "$(eval_gettext "Entering '\$prefix\$path'")"
 			name=$(module_name "$path")
 			(
 				prefix="$prefix$path/"