Mark strings in git-rebase--interactive.sh for translation. There is no
need to source git-sh-i18n since git-rebase.sh already does so.
Add git-rebase--interactive.sh to LOCALIZED_SH in Makefile in order to
enable extracting strings marked for translation by xgettext.
Signed-off-by: Vasco Almeida <vascomalmeida@sapo.pt>
Signed-off-by: Junio C Hamano <gitster@pobox.com>