Since sha1_to_hex is limited to SHA-1, switch all remaining uses of it
in this file to hash_to_hex or oid_to_hex. Modify update_remote to take
a pointer to struct object_id, and since we don't modify that parameter
in the function, set it to be const as well.
Signed-off-by: brian m. carlson <sandals@crustytoothpaste.net> Signed-off-by: Junio C Hamano <gitster@pobox.com>