replace: add --edit option
This allows you to run:
git replace --edit SHA1
to get dumped in an editor with the contents of the object
for SHA1. The result is then read back in and used as a
"replace" object for SHA1. The writing/reading is
type-aware, so you get to edit "ls-tree" output rather than
the binary tree format.
Missing documentation and tests.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Christian Couder <chriscool@tuxfamily.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>