Turn harbour into a reference lfs server

[rubyist]

We can turn harbour into a reference lfs server of sorts. It doesn't have to be able to handle GitHub levels of traffic, just implement the API in a simple way with a simple auth/storage backend.

• Provide some kind of authorization hooks
• Use a simple file store similar to alambic in enterprise
• Probably remove the S3 URL generation (unless we want to provide that option)
• Prepare for OSSing
• Name it

/cc @github/lfs
/cc @bkeepers for thoughts/processes on preparing for OSS

[technoweenie]

👍 For the launch, we should definitely focus on a local file store. We or someone else can always add S3 later.