find should follow symlinks

I was trying to sync a local repository on S3 (without archiving) and it just didn't work.
After a bit of digging, I found out it was only an issue with symbolic links.

It appears `find #{directory} -print0` in the `local_hashes` method need the `-L` option to follow symbolic links.

I didn't add a spec, because reading at them it seems you never really test on actual repositories but stub them. If i'm reading wrong or if you have any idea how I could test this, please point me at the right direction and a spec will follow.