merge-one-file: compute empty blob object ID
This script hard-codes the object ID of the empty blob. To avoid any
problems when changing hashes, compute this value by calling git
hash-object.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
authored by