Up to now git has assumed that all servers are able to fix thin
packs. This is however not always the case.
Document the 'no-thin' capability and prevent send-pack from generating
a thin pack if the server advertises it.
Signed-off-by: Carlos Martín Nieto <cmn@elego.de>
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>