document submodule sync --recursive
The git-submodule(1) is inconsistent. In the synopsis, it says:
git submodule [--quiet] sync [--recursive] [--] [<path>...]
The description of the sync does not mention --recursive, and the
description of --recursive says that it is only available for foreach,
update and status.
The option was introduced (
82f49f294c, Teach --recursive to submodule
sync, 2012-10-26) a while ago, so let's document it, too.
Reported-by: Per Cederqvist <cederp@opera.com>
Signed-off-by: Stefan Beller <sbeller@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>