unpack_sha1_file: zero-pad the unpacked object.
unpack_sha1_file: zero-pad the unpacked object.

This makes them easier to parse without having to worry about
running off the end, and allows us to treat commits as normal
strings.

destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git,destenson/git