fix "git fat pull" for fancy named files

Hi,

in this PR I've just added `-z` to `git ls-files` and the result is split at `\x00` instead of `\n` (as this is the new separator). 

A simple change but now we're getting the original filename back from git and are able to handle names containing spaces and/or fancy utf8 characters.

Feel free to request changes if I missed something crucial.