This was added back in
7e52f56 (gc: do not explode objects
which will be immediately pruned, 2012-04-07), but not
documented at the time, since it was an internal detail
between git-gc and git-repack. However, as people with
complicated setups may want to effectively reimplement the
steps of git-gc themselves, it is nice for us to document
these interfaces.
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>